I'll say the same as trooper1, always keep long term trooping in mind during your build. It would stink to do all this work and then have to fix or replace parts after a few months of trooping.
For example, on my scratch T-21, I left the sights off. Would it look a little better and be more accurate? - absolutely. But I found they were fragile and I didn't want to replace them constantly so I left them off.