So here's an idea: what if you ran a speedballish type mode with player classes. Electros and FS players can't move forward of their own 20 yard line and are limited to 300 rounds, mechs and magfed and AT pumps can move up to the 50 but can't grab the flag (likewise limited paint), stock class, regular pump, pistol or magfed can go anywhere and grab the flag.
One point for the first pull, one for the hang, no points for body count or kills. Hang by getting flag over the other teams 20 line or backline depending how it plays. Or use zone captures, or whatever. Mix it up ICC style.
Maybe add extras - pistols can use (size limited) shields, stock class are also medics who can touch a player to revive them. If you have the flag when shot you can respawn. I dunno.
So basically Overwatch paintball designed to give each style of player a fun role and with some kind of objective which you could mix up between field types. Would take some explaining and experimenting but could be cool.
That's the real issue though. Paintball players in my experience seem alergic to complexity. It would need a careful info campaign beforehand and explainer videos etc.