Apples and oranges, and even if they were both apples, they have such counterbalancing strengths/weaknesses and stats that it's impossible to decide.
Frazier played in three and won two national championships (Tebow has won two, could win three, as well as a Heisman). Tebow owns Frazier in statistics, Tommie never had very good stats. Tommie was considered a running quarterback, whereas Tebow is considered a dual threat (he won't really make you miss or break off long runs, but he is good for 5+ yards any play). Tommie was unable to play most of the '94 season, and also didn't play in the second half of a lot of games because we would always kill teams so badly (but maybe that just means that he had better talent around him, and he himself wasn't that great).
So many things that there aren't answers to, so why bother?