ok here's the verdict:
basically the whole class system is forgeted up in terms of balance. Recon outclasses sniper until you upgrade it to the second-highest and highest tier, where they basically go to stuff because the accuracy is 5x worse than the P90. the USP also outclasses everything in existence because of its perfect accuracy and no forced delay between shots. For the LMG's, the second teir is basically just like the recon in which it has the accuracy to outclass snipers, but the second you upgrade it to teir three it becomes useless due to inaccuracy. Snipers suck overall due to the scope and recoil, which serves to do nothing but limit your sight and screw up your aim when you could just be using a P90 or USP to get the same accuracy/kills with significantly less recoil.
In addition moving and shooting doesn't lower accuracy at all (esp noticable when scoping) encouraging strafing about 100% of the time. Snipers, however, can't strafe since they can't see stuff while scoped. Snipers also only get useful at teir 4 or 5 when you upgrade past those big-ass snipers that can't do stuff. However, even then they're UP compared to the rest of spamguns for reasons stated above.
Building is also screwed up because you can cover CP's with plates and overload them with health using the repair tool and rapidfire. Otherwise, its ok.
Upgrading teirs is a guessing game because you basically have no idea if the gun next is actually an upgrade and not a downgrade, making previous leaders have a huge advantage over new leaders because they know exactly when to stop upgrading. And the medic teir 2 upgrade doesn't retain the syringe making it a pure support class and unable to stand by itself as it would seem with the syringe upgrade.
Explosives seems to be the only class without issues but while I was playing there as leader for about 2 hours i didn't really upgrade it.
You also need to implement a "leaving battlefield" autokill because some just use the side walls as a sniper post. using it doesn't make them op, it just counters the original intent of having those sidewalls in the first place.
TL;DR: Get a new weaponpack or basically redo all the code in this one. I highly advise T+T/some projectile-based weaponset considering the style of combat going here, and to make kills less easy and more satisfying.
and please goddamnit playtest your own tiers instead of relying on others to tell you "oh this is the right way to go" since you are the one who's building the map and can tell whether or not its a good weapon for that teir.
and as a rule of thumb accuracy Annoying Oranges ammo count.