Be aware that to actually make Libs work you're going to have to spend a lot of certs and fly a lot. Libs have a lot of counters but with a good crew can do amazing damage.
Excellent starter videos by WyCliff here - especially for pilots. One word on airframes and utility - while Fire Supression can work with High-G, Turbo is required for running Precision Bomber in my opinion.
I'm not sure what to cert first but I think that's covered in the video. I wasn't really happy with my Lib until I spent about 10k certs in it.
1.) Work as a team. The most efficent and quickest way to destroy anything but infantry and ESF is usually a combination of Tankbuster + belly gun. Hence hold your horses for the right moment, you will get your shot. Communication with the pilot is key.
2.) Spot is your friend. This is true for pilot and gunner. Q should be your most valued button. It shows your gunner which target you softened with your tankbuster. Vice-versa your gunner spotting shows you the enemy on the mini map, which allows you to keep your gunner on the target, especially when it is moving. Consequently only the focus-fire target should be spotted if possible to simplify things even more.
3.) Prioritize Depending on the amount of AA you have to pick your targets. This is highly situational of course, depending on how many Aircraft are in the air and how organized the enemy AA is. For illustration we assume it is just our Lib against following AA:
Light AA: 1 BursterMAX/Skyguard/Turret and a couple of lock-ons. Go for the AA first, usually they can't kill you faster than you are killing them. After you got rid of the AA it's farming time.
Medium AA: 2-3 BursterMAX/Skyguard/Turret and/or a group of lock-ons. Your only option is to do strafe runs. Picking the target becomes even more situational, basically you take what you can hit. Ideally you will try to reduce their AA until it is safe enough to take out the rest in a direct approach and then farm again.
Heavy AA: Lots of stuff or very organized AA. Basically you can't approach without dying. You really only have 2 options: Abandon ship and join the ground troops or go on a suicide mission to take out their most valueable target (usually deployed sunderer). Flying with me most of the time means the 2nd option
4.) Enemy Aircraft first As soon as there are enemy ESF or Libs in the vicinity, I will always go for them first, since they are the biggest threat. I will always turn my belly to fight them, so stay on the main gun. The only exception is if I decide to “puss out”, then I will ask you to man the tail gun. Spotting is even more important when fighting fast moving enemy aircraft, so I can give you the angle to shoot them with the belly gun.
Dalton vs Shredder
First of all, Zepher is lame and only good for farming fights that are already over, but Dalton and Shredder can do that just as well. Forget about the Duster.
The Shredder is easier to get into than the Dalton, the flying has to be very precise though. The Shredder is really good in squad sized fights because you can take care of AA Maxes quickly and then reap the ground targets. TB + Shredder also kills Sundis almost instantly. Shredder somewhat falls short against multiple air targets though and requires backup in those cases, else the ESFs will just keep backing off and eventually overwhelm you.
The Dalton is harder to get into but performs amazingly against air and armor, good against infantry and meh against AA MAXes. The Dalton requires lots of practice to learn and consistent flying to stay good at.
If your gunner is really, and I mean really, really good you can farm armor Zergs from extreme height like they're nothing.
How to get better as a team
A dedicated crew is almost a must these days, the most important thing is that you can stand each other and your schedules somewhat match up so you can get in a lot of flight time together. The rest will come by itself, basic skills required of course.
Fly a lot, analyze why you died every time and try to avoid it in the future. As a pilot, always try to give consistent angles and never get into situations where your gunner has to hit every shot just so you survive - e.g. engaging multiple aware ESFs head-on (well, there's do or die situations sometimes of course) or hovering above a Skyguard - that just causes frustration.
Amerish is a decent place to start out, less population and lots of air ressources means you can fly somewhat more carelessly. Also, lack of flak means you can go for TB + bellygun combo against ground vehicles almost every time so gunner and pilot both can get maximum exp. Just don't stick to Amerish and farm 12-24 fights forever like so many other mediocre Lib crews.
When you enter a fight, prioritize targets - go for aircraft first (go for easy kills first, especially Liberators), then AA, then Armor - going for infantry usually is not worth it unless it's a huuuuuuuuuuge farm - or your PL needs you to carpet bomb a point. Once all vehicles are gone just move on or intercept reinforcements/protect sundis.
One word on Lib against Lib engagements - when you get the jump on another Lib, just put one clip of TB into it, then give angle to allow your gunner to finish it. With maximum mag size you can even 1 clip other Liberators but that doesn't work unless they stand completely still or are hurt beforehand. In any case, make sure you don't end up below the other Lib at the end of your TB run because otherwise you will probably die. If you see another Lib approach you, press control and afterburn away (turbo is essential in this) while giving angle, that should dodge most of the TB and allow your gunner to shoot.
See at 6:25
Generally though, if you notice another Liberator coming for you too late you're probably going to die.
Against ESFs: If there's just one ESF, concentrate on giving your gunner consistent angles. The easiest way to win - assuming the ESF doesn't start sniping you from render distance - if to just be aggressive and get above it. Whatever you do, never go below the ESF, keeping an altitude advantage is crucial.
Against multiple ESFs: Not going to lie here, the gunner has to get it exactly right/get lucky or you're going to die. Try to get into friendly cover, if that's not possible - if they come at you like lemmings just keep giving a good angle, if they engage in hover fighting put pressure on them and hopefully kill them one by one but fighting multiple ESFs who know what they're doing will most likely end in your death.
Against Liberators: It's basically who gets the jump on who first, a TB clip is never wasted and giving the angle is a must. If the enemy lib has composite armor be sure to go for the TB kill rather than giving angle for the dalton as it takes more shots and is way more risky.
Once the air is dealt with I generally do big circles at a high altitude, after the Skyguards and AA turrets are dealt with I get somewhat lower but still stay out of lock-on range (450m above ground).
In big zergs the shredder doesn't have the psychological impact of a dalton, but that's also a good thing: it's quite easy to focus on smoking tanks that are already being engaged, because those usually don't realize that they're being shot by a liberator and tend to only retreat out of los from our AV and jump out to repair, which allows me to finish them off unless they get 3 engies on it.
The shredder lacks the raw dps of a well-aimed dalton and its burst damage, but can still kill a tank with ease if there aren't 2 engies repairing it. Also, the lack of bullet drop and the high bullet speed make it useful up to render distance, while the dalton becomes harder and harder to aim with.
Against ESFs: your worse enemy is distance and transversal movement. Lure them into getting close to you and don't allow them to hover as much as you can. You don't have the 1-shot potential of a dalton, but you can easily get hits on anyone and slowly kill him even if he evades most of your shots. If you see one coming towards you, wait until they're close and then blast them. It takes less than half clip to kill an ESF.
Against multiple ESFs: unless they're real scrubs, run and try to find friendly air. You need a fairly long time to kill a pilot that doesn't hug you and the other ESFs will have an easy target in front of them.
Against Liberators: the pilot must keep maneuvering because a dalton just needs 3 hits while you have to put about 2 mags into them (goddammit SOE ಠ_ಠ ). Keep your distance as much as possible and give your gunner a good angle… and try to stay above them as often as possible.
Against AA: A solo burster max is a joke, just find him and put some bullet into him; multiple bursters are a pita, but you can sometimes charge at them and kill them off if they're exposed and there isn't heavier AA around (tanks count); a solo skyguard is just an xp pinata ready to be popped, you can tank it and the shredder can oneclip it if you're close enough.. same as above for single AA turrets; against lockons… you can't do shit beside staying above 450 meters. Good luck with that in southwest indar; except for walker sundies anything else won't really hurt much and you can kill it before it does too much damage
Bonus: A short video I made back in November 2013.
Regarding the airframe choice, you can make them both work, depending on your style. With the precision bomber you will use the turn left and right to follow targets, with the high G you will use the nose up and down. I do prefer high G for everything as I'm more of a gunner focused pilot and I like to use the power of the vertical thrusters for most of the maneuvers. I also recommend using afterburner since the buffs as they will save you more often than the other tools and it will also grant you more kills by catching up to targets.
We still have our dual point of view lib flight raw footage vs future crew which is a good resource to see how different maneuvers affect a gunner (vid is secret and unlisted on youtube so INI eyes only ofc due to outfit chatter).