Yes, originally they were just dispicable. Then he decided that it wouldn'tbe all Dwarves, just the ones who sacked Doriath who were bad guys. By the time of LotR they had matured (by which I mean not in historical, but fleshed-out-character terms) to be a race with a wide variety of individuals, noble, proud, greedy, and corpulent in them. But certaqinly the good Dwarves, such as Durin'sline whihc produced Gimlik Balin, etc, must have been liked by Tolkien. As for the not so nice ones (and note that even they're not "just bad": they served Sauron in the Second Age, some did, and yet didn't Dwarves from all Houses help Durins' get revenge for the murder of Thror?) , well, Tolkien didn't like not so nice Men or Elves either.
