I feel that these 3 would be middle tier, if that exists, but not top tier HOFers. Both Joss and Waddell had a few years of greatness, but their overall careers are too short. A top tier HOFer needs to have a fairly lengthy career to put up the numbers to be truly upper echelon, in my book.
Brown had a fairly long career, but he only had a 6 season stretch of 20+ wins, and this was during the deadball era when 20 was attainable for average pitchers.
All 3 were great players and I like many of their cards, but when you compare them to true top tier pitchers like Mathewson and Johnson, they just don't quite stack up. Joss and Waddell both had the potential, but "what if" doesn't get you top tier.