The OG professor, Oak! Except when he comes to stay at my Villa, because he doesn't leave for days! >:/
And who the heck are these guys?:
Professor Krane
Professor P
Professor Hastings
They're the profs. from the home console/spinoff games. Krane comes form the GCN game Pokemon XD (Colosseum didn't have a professor, and in XD Krane doesn't give you a starter Pokemon (whether he gives out any at all is unknown, but maybe not given Orre in those games is still recovering and only getting wild Pokemon coming back), but he instead works on helping build the system to purify Shadow Pokemon and teaches you how to snag Pokemon, maybe...?
Prof. P is from Trozei, and Hastings is in the Ranger games.
Anyways, I voted for Oak - he just seems to be the most like-able of the lot for me. He also seems the most professor-like - he does know his stuff, and according to various canons was a good battler in his day as well. Compared to the likes of Elm who lets Silver steal a Pokemon from him, and had no idea about Pokemon eggs despite being an authority on the subject of Pokemon breeding... =/ Birch gets chased by a Poochyena/Zigzagoon of all things and needs your help with defeating it... Rowan I suppose is decent though, with an interesting personality, and also some amusing jokes in Platinum.
Krane is ok, but I never particularly liked him, never played Trozei nor saw Ivy in the anime... Hastings was ok too, I suppose, but for me Oak wins.
Never mind his haikus. =P