Just went back to playing ME1 and the weapon cooldown system can essentially break the game as you progress to the point where you don't even need to use character powers. With some weapons you can just hold down the fire button and keep spamming from a distance and not even worry about powers.
Then the other side were you keep getting hit with Sabotage spam making your weapons overheat forcing you to wait for the cooldoon (which is rather lengthy on most weapons)
So thermal clips serve a gameplay purpose to encourage power usage and have people focus more on aiming to make sure each shot counts (something they allude to in the codex, just shows that gameplay needs to be the priority as the levels in ME2 would have been rather boring if you could just spam weapon fire).
No one claimed that ME1 shooting mechanics were perfect, the idea certainly needs some work, and double friction-less materials shouldn't be an exploit.
And as I mentioned, something like the active heat management of Battlefront is not a bad idea - it respects the lore, and also inserts something very similar to the sacred concept of reloading.
As for power usage, personally I almost always play "casters" (Biotics, Vanguards, Engineers, etc.) anyway and use powers more than weapons.
But since "powers" in ME are mostly about stripping certain defenses and crowd-control, and even self cooling weapons require management of fire,
there's very little "danger" of powers being completely ignored.