I put 28's or even 32's on our tandem. (I really prefer the 28's.) Because of the brake problem you mention, that requires letting some air out to get them out of the bike, or not pumping them up all the way until they're in the bike. It does work though, and there's still clearance to go to at least a 35mm tire.
I use 25mm tires on my single bike. I'd like to try all the tires, but I know if I did, and then decided on a favorite, by then it wouldn't be available anymore anyway. So I just keep researching it from time to time and occasionally trying another one based on the research. Of the ones we've tried, my current favorite is the Continental Grand Prix 4000 with black chilli (their brand name). There are very few tires that have lower rolling resistance than these, and they are also quite good in the puncture-resistance department. The Michelin Carbons were also good, but have since been replaced by the Michelin Krylion Carbon which I have not tried but presumably they're at least as good as the older Carbons. The Continental Gatorskins are outstanding for puncture resistance, but their rolling resistance is 50% higher than that of the 4000's and they don't have as nice of a ride. I've been getting a flat every couple thousand miles with the 4000's, even with the ultra-thin 49-gram Performance LunarLite tubes which I use to further reduce rolling resistance.