Commandos spawn with their nade on cooldown, Stormtroopers do not.
Thats kinda the whole point, in case you missed it
That and the fact that inf commando squad DPS on spawn is almost half of current stormtrooper squad
One has a mini nuke with sorter fuse than normal grenades that could easily be abused for squad wipes the other has DOT grenade, that is the point in case you missed it.
I would also suggested you check your numbers about their DPS.
In addition infiltration commandos can reinforce to 5 men, get access to lmgs (and ATG), get camo bonuses and have one of the highest tenacity in the game among other things.
I am not sure why you want to compare the units.
Finally if in your opinion DOT grenades and light gammon bombs are the thing than you should have no objection in my suggestion of replacing all explosives grenades for these units with DOTs, cooldown or no cooldown.