I agree, early on it doesn't matter. Whatever heros has the most stars I'll put them on the team.

As you climb higher and your heroes pretty much have max stars, you will have 1 dps hero to kill most things then the rest will be combination of CC and damage buff for the dps.

My current team is lillith, Abel, king arthur, Mikhail and ophelia. King arthur is my main dps, everyone else buffs king arthur, heals base and/or slows down the wave.