I'd suggest that those seeking a Generihawk to base their campaigns in check out the tiny OD&D setting Thunder Rift. It's basically the implied setting with a map, with all the tacit D&D assumptions not only presented intact, but spelled out explicitly in many cases. In terms of a generic backdrop for D&D shenanigans, it outshines even Greyhawk. Heck, you could even put it in Greyhawk without modification.It was and is a base world with not too much detail so you could steer it anywhere you liked.