I got my KH29 for mixed muni and commuting about 3 miles. It’s been my main muni, and worked OK for riding road. Sounds like it would be a good fit for you.
Comparing to other sizes: I started muni on the 29, and now also have a 24. I prefer the 29 for muni because I prefer rolling, and the 24 just feels way too slow for me. I suppose I also like looking down on mtb’ers. 
I got a Coker about a year after the 29. As soon as I got comfortable on the 36, I stopped using the 29 for any road rides. I also really like the 36 for relatively easy xc muni (mostly double track without major climbs), but would choose the 29 over the 36 for a muni focus.
Brakes: I recommend them. I don’t use them all that often, but they absolutely expand the terrain I can go down on both 29 and 36. I suggest starting with a v-brake. For less than $30 it’s a good way to find out if you like brakes. See here.
Edit: Also, I think your question is not so much which one you’ll get, but rather which one you’ll get first. Once you’re thinking about them, I suspect you’ll end up with both eventually. 