So games like Warcraft, Starcraft, and Command and conquer have predominantly dominated the RTS world for like 25-30 years. The basic mechanics is you buy individual units and then give them upgrades to make them stronger. This has been the basic format since the beginning.

What if you could have a different spin on it. What if you could create an RTS that creates whole units, and instead of just upgrading a unit, you outfit them with options. So say you have a standard unit of 9 guys with assault rifles, you could give 2 guys shot guns, 1 guy a sniper rifle and 1 guy a rocket launcher. maybe give the two shit gun guys flash bangs and the sniper a claymore or something. maybe the assault rifle guys get better armor and drag grenades. Then they are joined by a combat medic who helps reduce damage or heals damage over time.

And this unit must fight until it's either dead or has gained enough experience that the surviving unit can be refitted with replacement units or advance into a specialty unit.

just spit balling ideas.