This would apply to both the Schaller and the OFR. If you like to pull up on the trem, the bolts on the back of the bridge have the potential to destroy your finish there. Recessed, there can be a thin piece of foam there so that if you get too into whammy mahem, then the wood is protected. Also, if you don't recess, then you'll need an angled neck slot. If you don't pull up very aggressively, then it would depend mostly upon how the playing position feels to you (higher or lower bridge). I personally like the lower bridge level. If you're not sure, then go into a store and try out a couple, recessed and non-recessed.
As far as the nut width, that depends upon your preferences.