Todd,

I put up drywall, but that is your call. I suggest that for lighting,
be sure and consider track lights over where you think your tools will
be. If you add more power tools you can add to your tracks and put
light exactly where you want it. I used halogens over the work bench
and finally I could read my dimensions even in winter when it was dark
outside.

I also suggest you do the ceiling first. I like the idea of OSB. I
used drywall and used pegboard liberally. I hate having to look for a
tool and know I have it but can't find it.

Bill in New Mexico