I was going to suggest an "Alt-toberfest", but if you can't ferment in the low 60's that'll be a problem. That said, with a swamp cooler I could easily hold my fermentation temp in the very low 60's for the first 3 days or so, which is the most critical time for low temp control.
Another idea is a "fest" type wheat beer. I have had one on draft at an O-fest several years ago made by (I believe) Paulener. I'll have to look that up to be sure. But still, you are going to want rather cool fermentation temp for something like that.
You can get a relatively clean tasting ale with the Chico strain (WLP001/WY1056/US-05) at ~68 degrees. You could replace any o-fest recipe with that strain. Personally I believe a cooler fermentation temp would still be better, and you really need to lager anything like this for at least a couple of weeks, if at all possible.