Hello Fal,
well i have some great ideas that you could put in the game just some suggestions
1. Some sort of Plot or Story mode
2. Mixed classes (for example) medics get the upgrade and they can also drop ammo like the support can etc.
3. more guns and cheaper prices on maxing things
Anyways....
Thanks for creating such a beastly game

2) Mixed classes sounds kinda stupid. No offense.
3) More guns is good, but I think everything should stay the same price wise.