A more serious point tho, locking say fighters to pilot class only could lead to alot of players being pilots and then just hanging around camping for next spawn.
Easily solved by making them pick-up kits. Spawn as, say, a tank hunter, and if there's a fighter nearby, pick up the pilot's gear and jump in. Even better, leave a regular trooper kit next to the pilot kit so that you can change back if there's no fighter or tank to jump into.
Having a class with that little flexibility leads to staleness in my eyes, and risk impacting gameplay more than the unrealism of stormies flying TIEs.
I actually liked the inter-dependent classes of GC. The Scout, say, was a master of stealth, recon, artillery spotting and sniping with his camouflage tent, sprint ability, and accurate sniper rifle. However, he had no side-arm and no cross-hairs for the un-scoped view of his rifle, handicapping his close-combat skills. He also had nothing that could damage armoured vehicles (I liked how tanks and AT-ATs were impervious to lasers and blasters).
I liked that setup. You had the versatile Trooper that could do damage to both troops and armour, but pretty much every other class was so specialized that they needed to work together. I loved it as it kept most players going Trooper (realism) and made it so that everyone depended on each others (game-play).
Just to encorporate a pilot class?
No, to keep infantry from flying fighters and driving heavy vehicles. As was said, nothing's more annoying than someone using a TIE Bomber as a personal transport, flying it to where he needs to be and then landing it and jumping out, leaving it to rot and eventually blow up when it could've been up there bombing Rebels. It's also annoying to destroy a tank or fighter only to be killed by the heavily armed grunt who jumps out of it.
Also, there's realism to think about. I may have pointed out once or twice
that stormtroopers don't drive AT-ATs or fly TIE Interceptors.
The best idea so far is to have you morph into a pilot or tanker upon your entering an "advanced" vehicle, and then stay as a member of that class even after you've left it.
As a side note, I'd like to add that I want to see the pilots and tankers drive/fly their vehicles only. I hated Battlefront' approach of having them take the roles of Combat Engineers/Support Infantry. Pilots and tankers do not run around distributing ammo, placing det-packs, and healing wounded. They fly aircraft and drive land vehicles. They can have some class-correct equipment like signal grenades, binoculars, and repair tools, but that'd be it.
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage."
--the awesomeness that is Boatmurdered.