Starts off with Time and the Rani, the worst Doctor debut ever. Twin Dilemma is a bad story, but the characterization of the Doctor, the unstable, unpredictable madman, was great. TatR has a shit script, shit production AND a shit Doctor, both writing and unfortunately, acting wise.
Fortunately, McCoy and the character were nowhere near that bad for the rest of the season. In fact, he can actually be pretty good. By Remembrance of the Daleks, he's a genuinely great Doctor. By Season 26, he's my favorite Doctor.
By the time we get to the Virgin New Adventures, he is THE Doctor. The definitive one. Been re-reading many of my favorites in this series (surprised Lonemagpie said earlier he disliked 7 as he did quite well with him in Sanctuary, although on the other hand, he isn't anywhere near as magnetic on the page as Guy and Benny) and he's just got everything, everything that makes me love the character of the Doctor rolled up in one amazing package. The light, the darkness, the eccentric in-between, everything.