I'll throw my two cents in here and although you said you didn't want specific recommendation, I'm going to make one.

I would be more concerned about the quality of the tire and it's construction rather than width. If you put really skinny tires on a hybrid they often end up looking funny due to their large amounts of clearance. I'm running Vittoria Randonneur Hypers in 32 mm and they are fantastic. Their sidewalls are 120 TPI (threads per inch) and they are really light. On my velocity dyad rims they actually measure 34mm in width and are very fast, very comfortable and corner really well. On top of that, they are pretty affordable (as bike tires go) at something like $35 each. Vittoria did change the name this year but it's the top of the line Randonneur tire on their website.