I'd like to put in a quick plug against milling the head for anything other than what is necessary to make it clean and level. Not only do you permanently lose piston to valve clearance, but you have to deal with correcting cam timing and whatnot.

You can get .2 more compression with p30 (JDM b16) pistons, and .5 more compression with pct (CTR) pistons. Both will cost you about the same as p73-00 pistons, give you the compression you want, and you won't have to mill.