Back in the day my team did a huge woods event with a similar idea. It gets to the heart of what OP is suggesting, if not the exact same at all.
Open format 250 cost to play w/ full rental equipment and air/team paint
Each get one case of paint, team had 10 cases (ended up being 50person teams 4 teams)
Teams won points by controlling certain bases. Ammo ATVs has to be used to movie cases of paint around and could be captured, no carrying cases.
What we did was group everyone by marker when the game started. It was a mainly rental group which helped. So we had about 120 rental tippman carbine style markers. We put 30 of these players onto each team.
We had 20 pump players, with various types of set ups, we split them up evenly.
20 milsim guys with milsim set ups, we split em.
40 mid - high end electros (ion - egos, dms, timmys, we) and 10 in each
Everyone had a case, but it was a 10 hour game. The case went quick and the teams were the only ones who had ammo. They had to decide how to give that out. They could get more ammo by doing certain missions. We also had first strikes would could be gotten through certain missions. FS could be traded for ammo, some teams had a policy if you got them you had to trade for normal ammo, even if you COULD use them.
2 teams only allowed their pump players w/ FS setups to use them. 1 of those teams had players shooting FS the whole time (all pumpers).
Most teams allowed their best marksmen (the older DM/timmy/ego/ect owners unlimited ammo, but heavily limited the younger users of the same markers)
One team gave Mag users all the ammo they could shoot, they all allowed pumpers to keep fillin up.
But yea, even with no role playing, people played roles. If you were out, you had to go to the main respawn area to get a new band. You'd have to throws down (and tear off arm so can't be used). This means you are back far from the front lines of any mission or base and don't know if your team controls the route back. This forced people to play a very specific way, combined with the paint situation.
Pumpers generally played as "sniper like players" moreso when they had FS. They would scout run, run through enemy territory and try and stay unseen. They would not be missed on the raging front lines, but could do real damage from being those lines if they slipped unnoticed in the thick of battle. Some of the milsim players were doing similar things, but often the crack of the blowback tube made sneaking hard.
The older high end owners held down the main battle lines. They didn't stand up front, but they held the line of control for each time, as the team took ground these players would be playing the best positions for cover while suppressing the enemy.
Younger high end electro owners would often be given paint only when committing to a mission that would send most back to the staging area. Ion users seemed eager to offer to run through lines, draw fire and get a few elims for a little paint, and almost always followed through (I have an ion, not hating, but in this case were all young kids).
Mag users got treated well. The quality combined with lower speed meant they could be trusted with paint, and people assumed they knew how to play. They held down pain lines. They skill helped stiffen the line, while the lack of speed made them expendable in a way the most talented high end electo users were not. One team lived and dyed by three teamates with DM11's. The few times someone got them out, they lost massive field position in that area. Those kids nailed me like 4 or 5 times, for my once back on them.
The rental users were given paint when they did well. Someone who was getting a few kills or showing good judgement got more paint. More had enough paint because they showed the sense to conserve. They held the line with the mag guys because there we lots of them. The ion level markers were best for advancing as they are light, small and can rain paint if you get a good angle on a few people.