First of all, I'd like to start by noting I'm a fragile newb, so please keep flogging to a minimum if possible, but onto the requests/suggestion things...
1. I had tried playing a paintball game for Half-Life, and it was interesting because you started with the generic pistol, and as you captured the flag, you made $50 dollars, and everytime it was returned, your team made $300 dollars apeice. As you gained money you could press a binded key and (in your base only) you open a menu which allowed you to buy CO2, paintballs, different guns, and miscellaneous stuff like a scope, laser sight and grenades. It might be interesting to have this implemented, but have it optional so when someone makes a game it'll say [Menu] or something. I suppose that would fall under realism. (Braces self for beating)
2. I guess it would make things cheap, but like in all FPS, there should be a hidden area or something that could be reached if you could find it or whatever, but you could get an auto-topper, which wouldn't mean non-stop firing, but just maybe a second or two.
3. The grenade is cool, but maybe instead of a random fiesta of paintballs which can be set to extremely cheap amount of paintball flying everywhere, you could just have it spin and look like a smoke bomb (like in Extreme Paintbrawl) and anyone withing a settable amount of feet from the grenade would be eliminated with a default of 15 or something.
4. Maybe some type of weather can be put in like fog, or rain, that would make things difficult for everyone, or maybe just make your mask have droplets on it so it makes you agitated.
5. I've seen all the "Plz add new markers" posts getting shot down, but It might be interesting to see the more unique markers such as those carried by rap4.com, like the grenade launcher, a player would have only 6 shots, but it would be almost like a shotgun, firing 5-11 balls, and having a crappy delay between shots to stop from mass destruction. Also, the markers that imitate real guns would be interesting since you would have a really accurate gun, but only 16 shots per clip until you had to reload as they don't use toppers.
6. I see that we have all the basics modes of an FPS, but also what might be an interesting idea, like I think it was in Timesplitters 2 or 3, is a scenario game where you had to disarm all the AI controlled opponent's and fulfill quests as they came along. It might be fun to have to use an airsoft rocket launcher to take out a paintball tank just like at a real scenario game.
7. As for the thing about models/skins, maybe you could just have a character select type option, and during every new release include the best character/skins submitted.
8. As I can see from the glares I have overstayed my welcome, and I shall return to my world of pretend. As for my ideas, if you think they're good, that yay for me, and if they all suck or have been previously rejected and I've noobishly dug them back up, then I take my flogging with grace, and a girly scream.
Thanks for reading, or what not...