My garage is detached from the house and it has its own 200 amp service, but it's at the opposite end of the building from my shop, so I ran a heavy wire down and put a subpanel in the shop. From there I divied up the circuits, including provisions for 220v circuits.
I have led lighting. At first I thought it was too much, looked like a tanning bed in there... but now I'm glad I put in as much as I did.
I still want to put some good lighting under my upper cabinets to eliminate shadows on the bench.
Oh yeah, cabinets.... start watching Craigslist for used kitchen cabinets. You can find some really good deals. I ended up getting 3 different kitchen's worth of cabinets that all match and put some in my bow shop and the rest in the upper garage. Love em. Ya never have too much storage. I also got a bunch of shelving from a Rite Aid store liquidation to store bow wood, jigs, and supplies on.
My shop still isn't done, but at least now I can work in there. I still have a big chunk of bowling alley I'm going to use to make another bench. It has a perfectly smooth and durable synthetic top. This bench will be heavy duty, perfectly flat, with bench dogs and a pattern maker's vice.
A/c.
Electric heat.
Dehumidifier.... doesn't run much with the last two in there, but sometimes in the spring and fall, it's quite valuable here in western pa.
I don't have a dust collection system yet, and I might not bother since I get by with a big shop vac, but it's something else to consider.
I have almost all of my big tools on mobile bases so I can move them if needed during use, or push them back out of the way.