I have a vision doc which I used to help me develop the game, with the central idea being an ugly, conniving evil wizard who corrupts/manipulates beautiful women.
If there is a single inspiration for Greely, it is probably Grima Wormtongue from LOTR (You can see the Ralph Bakshi and Peter Jackson versions below). However, I was also heavily influenced by Sid Valentine's Cohabitation which features a fat, balding manipulative MC.
Disney's Jafar and Don Bluth's Rasputin also fit the mold of manipulative evil wizards as well, with lecherous undertones. I took many other inspirations as well such as Jabba the hut, Grolokk by GA Corman, Slave Lord by Pink Tea, Dark Lord's Trip by Logan and of course the Akabur trainer games. (I have multiple documents full of pages similar to the below).
Gargamel's design was something of an overt inspiration since he is a balding, cowardly, evil wizard, but even though Greely is fat, unshaven, bow-legged, has dark eyelids, moles and is hunched with curly hair and a pig nose, the Gargamel look still really comes through strong.
I don't mind the connection, which is why I used him partially as inspiration. Although, it is a bit ironic, since Gargamel was kind of an after-thought for Greely because it fit with the character being bald, but from the feedback I've received, it really seems to dominate his design.