0 offest should work fine. adding a spacer will put that wheel in the negative offsets. so unless you are looking for more poke outside the flares then no need to add spacers.
I can care less what audio comes in it it will get swapped out for some focal or something nicer anyways. I currently run focal flax in my current rig.
Amber is good for bad weather situations like heavy fog/rain to cut through the bad weather. If you notice when you drive in rainy conditions white light tends to washout.
Well I would presume the sae are the only street legal ones since the sae have some what of a light cutoff in the lenses. I run the saes on my current rig the driving/combo you might be able to get away with but the wide cornering I would say no Atleast not on a street with vehicles around.