Unless you plan on relying on Claymore, the others don’t have a limited aoe attack ratio (the reason for Falcon). Sapper 3 is still fun, but you may end up having doubts as you’re running around, waiting for the 40s cd. Doing ~2.5k on a Harugal is lovely but that’s the only skill you’ll have time for in the Prison, unless you end up with an awesome team that gives you enough time to set up your Claymore and still hit the mobs with it.
QS - if you’re going c2, why not c3? c1 might be great for a filler though. There are so many times I wish I had soft taunt skills to make solo farming so much easier, but there are also times when I was grateful for taking Ranger for that Barrage.
For ideal Falcon builds, there’s the one from the first post in the [Guide] thread? Seems alright, but then again I am a boring person who goes straight for the AoE and nothing else.
Scout’s not bad - have you seen that video where the Scout ‘tanked’ during the mission? That is hilarious and might be useful since I find myself being the off-tank quite a lot during match-making. The few swordies I partied up with never tanked ><
Fletcher can also be a good filler rank since they have one AoE skill, Crossfire.
All these builds will end up depending on what your friends, if any of them are playing with you, will go. Random matchmaking can get extremely tiresome, although you can still go for pre-made parties.
If you have a Peltasta friend, go for the AoE and watch him get tired of you making the money while he sits there pressing one button every 15 seconds or so. Grinding has never been more fun.
If you’re going to end up solo-ing a lot, AoEs are grand but you might want to aim for really good single-target DPS skills. There are a lot of bosses, so the faster you get through them, the better your questing experience.