The first option is something I’ve talked about before; Adventures Great and Glorious™. It would cover rules for large-scale warfare, large-scale economics, political maneuvering, and dynastic considerations. Intended for use with Adventures Dark and Deep™ but compatible with most OSR-type games, of course.
The second is a full-blown fantasy setting with gorgeous poster maps, a gazetteer-type guidebook, and so forth. Since the World of Greyhawk Fantasy Setting seems to be closed to the gaming public for the foreseeable future (officially, anyway), this would be my attempt at making something similar in concept, but taken to its logical conclusion. Again, it would be lite enough in mechanics to be usable with most OSR-type rules.
The third is a series of smaller adventure modules. Some would have arcs connecting them, some would be location-based adventures that exist more or less in a vacuum, some would be larger and some would be smaller.
And, of course, there are probably a dozen things folks might be interested in that I’ve not listed here. Feel free to make your suggestions in the comments.
Thanks for your input!
Update: Obviously the polling gadget is the work of the devil, and doesn’t function properly. I’ve seen votes disappear before my very eyes. So just sound off in the comments here. Thanks!