Well most people I know ride 23's and 25's around the city. The kilo doesn't come with an ideal front brake, the caliper actually drops below your fork forcing you to use a max 25 with the stock front brake. If you change the caliper out, the fork itself is capable of definitely 28's and I would bet 32's. I'm a small guy, so for me I don't have to worry about my tire size, so this would be better answered by someone closer to your size, but I'd bet a good set of 28's with reinforced sidewalls will be more than proficient for you.

What about the completes don't you like? Specifically the Schwinn, Redline, and Kilo, as those are the ones below your max budget leaving you room for changes.