If the players are in the right mindset...medics in-play add a great dynamic to the game.
Mil-sim...doesn't having someone wounded (vs. dead outright and then they magically disappear and reappear), needing care/security, tying up resources/time/etc...better simulate what might happen in battle?
Some medic variations that have worked quite well...(some of these are different rules mashed together)
1. Wounded player must drop (safely) where they are...call out for help regularly
2. Wounded player can only be moved when in contact with 1 (up the number to 2 to tie up more resources) healthy player. Healthy player must "drop" wounded player to engage enemy
3. Wounded player must be moved a min of 50yrds directly away from the firefight to be treated. If encircled...no treatment is possible. If left in place for more than 5min...they "bleed out" and die.
4. To heal someone...the medic must have both hands on the wounded player for 60sec without pause...and then tie a "bandage" in a visible position to one of the wounded player's arms/legs. Cheap rolls of gauze are easy/handy/cheap to distribute.
5. When you're out of bandages...your wounded bleed out and die in 5min. Teammates can pass bandage supplies around...or not if you want to make things a bit more complicated. Or a wounded can only be healed with their own banadages...but in practice it's easier since the medic knows where their stuff is already and can have it in hand.
Issues that come up...
- 60 sec counts can be done "too fast"....up the time then to 2 min to heal someone
- can stall game where there isn't enough attrition....once guys get it figured out, sometimes there's not enough lull/lag to get guys back in the fight, and so the opposition can't fully exploit the reduced forces
- everyone needs to be clear...it's quite possible for misunderstandings to happen when someone shoots someone "dead", but then ~5min later the guy is back in the action. Seems like cheating if everyone isn't on the same page and doesn't have their brain switched on.
Huge, huge pro to using medics...is the challenge of managing resources and NOT having guys head back to some far off respawn point, never to be seen again. Keeps the game flow going...and sharp game hosts/control can alter things in play to avoid hangups.
For a shoot'em up skirmish...I wouldn't bother.