I am GMing a large and tough group in combat and I thought I would share a few ways I deal with it.
First, be generous with setback dice. Any rival or nemisis with a group of cannon fodder, er, minions will have some sort of plan to win a fight. A few of my favorites are:
Grenades
1. Smoke, 1 setback for everyone without special detection gear, a ubese tactic.
2. Tear Gas. 1 setback each for smoke, burning eyes, and breathing problems, the later two last 4 rounds after exiting the gas.
3. Glop. Found in a supplement. Immobility.
4. Stun. Not setback but still a great start.
Cover. Every enemy group should have it unless they were ambushed.
Ambush. Any enemy on their home turf should use this early and often. Start with a grenade, stun is the most feared by my group. An explosive charge or a mine works well too. The group should never get too cocky about how tough they are.
Squad rules. Give the minions a single light repeating blaster. The leader takes the hits on the others first. Devide the minions differently each round to keep them off balance.
Take every advantage. Everyone knows wookies hate stun, stun them. Minions on rooftops at the best range for their weapons. Drop grenades from above. Add a long range sniper when you get them in the open. Shoot the roof over their heads, the bridge under their feet, the fire hydrent or steam pipe next to them. Lead them into a room with turrets. Use comms to coordinate a hit from all sides like Lando in Empire Strikes Back.
Use one or two each fight except stun, use it often, even bad guys have use for prisoners.
Hope this makes more sense.
Please post your ideas here as well.