To be honest, this is mostly about GSBW, but it would be nice for any non-random powers that affect more tiles than the exact tiles you select, especially if the powers have varying shapes.
Sniper Rifle and Pistol both change shape as you add ranks, so it would be nice if all the affected tiles were highlighted somehow as you choose your “target” tiles.
Hood’s Twin Pistols could also benefit from this, even though the shape is constant. It would help in planning cascades.
This would also be welcome for powers like Inferno and Blammo (specifically the “hole in the center of the board”), but since there’s no “confirmation” step it might be trickier to implement.