McCoy isn't my favorite incarnation of the Doctor. They made him dark and disturbed. He only stood 5'5" or 5'6" tall and he carried a silly umbrella with him everywhere he went. After they hired such a short actor and gave him a silly umbrella, it seemed unrealistic for him to be dark and disturbed. His umbrella had a ? mark for a handle. That made it even sillier.
Batman is dark and disturbed but he wouldn't be if he was 5'5" and carried around an umbrella.
If they had given McCoy a walking stick instead of an umbrella, it wouldn't have been as silly.
Colin Baker should've been the one who was made dark and disturbed. He was bigger than McCoy and when something went wrong with his regeneration, he tried to kill two people. That sounds pretty dark and disturbed to me.
I give Sylvester McCoy's incarnation a 2 star rating.

Another fantastic actor to play the Doctor.  His interactions with Ace were superb: more than just a companion, she was a student of the Doctor's methods, and there has never been a greater interaction of the Doctor and a companion (The Tennant-Rose crap was all just hollow, boring sexual tension).  BBC had some great writers back then.  Where did they all go?