Hey guys, I'm having a little trouble with Marcus in my most recent playthrough. I think this has been a problem in the past too, but I never bothered with such a large party before, so I never noticed as much.

What happens, is I'll find a random encounter, raiders or something, and nine times out of ten, Sulik will rush the enemy with his sledgehammer, only to be torn to shreds by Marcus's minigun. Or Cassidy will load on the map right next to Marcus, and be, well, torn to shreds by his minigun. Or Lenny will... you get the idea.

I've been thinking of playing with my combat controls, but I was wondering if there's an ideal combination I can use so that I won't suffer a total party kill from friendly fire AGAIN?

Tell him not to burst fire. Alternatively, give him a weapon incapable of burst fire (he's competent with energy weapons like the plasma rifle and pulse rifle).

Thanks, I'll try that.

Flamethrower perhaps? (Marcus will need to get close and hopefully reduce the amount of friendly fire possibilities)

Marcus + Close Combat companions don't mix. Give sulik a SMG.

Give him a power fist or a super sledge, and watch the bodies fly.

Or just get him and no one else, during each encounter either you will have first turn or you will have second turn after the first enemy.
Gives you well enough time to high-tail out of his way.
But if you're going for multiple companions then yeah make him change the weapon because he's too overkill with burst weapons.

My method of dealing with this problem is to give Marcus close range weapons and all the other members of my group range weapons. Remember, what ever you do, don't give grenades to Marcus, if the enemies get too close he will ended up killing you and everyone near you.

This I gave him a plasma rifle real quick as he seemed to like killing me with his minigun several times in a row.