Looking at the Stormtrooper expansion, seeing tactical scopes, and seeing the Precise(1) rule native to the Stormtrooper, I am going to assume that Precise(1) + Precise (1) stacks together to Precise (2), otherwise there is no point in tactical scopes on Stormtroopers at all.
Based on that assumption, I think Stormtroopers are going to want very badly to run up really quickly and dig into cover early. Their shooting is apparently weaker (white dice) which if the movies have taught us anything, is to be expected, but the ability to reroll up to 2 dice with an aim token would help that considerably.
I expect to see Stormtroopers pushing hard to get in a location so they can then set to work laying down the pain. I think Veers may hand out aim tokens to nearby units too.
The point is, I expect unsupported Stormies to want to hunker down in cover near an objective and we may actually seee some Rogue One level, not terrabad Stormie shooting.
Do they have an offensive surge conversion?