That's a good price given all that.
A valve clearance check and spark plug change alone has got to be ~$500. Shops typically charge ~$100-150 for a serpentine belt replacement.
The only other things IMO, that would have been good to do are a trans, plus front and rear diff drain/fill. I actually like to do those just before 40K miles.
With that list, I'd say you did good!