Some ideas from me :)

[Leonid]

Hey all

1. Make option to upgrade weapons from level 1 to 5:
2. Upgrading is can be same as apparels(you need find more schematics via fixed places/missions/rivals).
3. Add weapon parts as another resource for upgrading weapons
4. Same goes for weapons parts
5. Make a kinda black market for trading weapons and rewards for doing some daily missions