I think Tate might be a bit too big for Tommy and can win on points, before John's Chin was found out by Weaver and Berbick, and was John suffering from some thyroid condition at this stage ? Tate was not at all bad for a big guy, His wins over tough Big punching south afircan duo of Gerrie Coetzee and Kallie Knotze, allowing for Gerries inexperiance, showed him to be quite skilled and mobile, Tommy was tough and skilled in his own right, but a cruiser by modern standards, and i think John, when fit will have the size to sway the fight his way, Tommy may actually be the better fighter but as stated, think that all things being equal skillwise , The tale of the Tape definately favours Mr Tate. i think he can win on points. As for Weaver, Tommy would not be a such a hight, reach, shortfall here, and has distinct advantages in Legspeed and manouverability, Mike can certainly Punch, but tends to throw big Single Shots, Tommy can certaily take a punch, and has the manouverability to find an escape route from the much more static Mike, If Tommy though Joe Louis was a Shuffler he might think Weaver is stuck in Treacle, Mike had a good Jab when he used it, but so did Tommy, and Weavers Left Hook is always the Danger, but if you Box Mike, and do not get into protracted slugging with him, then Mike often slipped into a cruise control output, with little sense of urgency, I think Tommy would stick to the "Handle with Care" script, it worked against Max Bear 1 out of 2 i think it would work with Mike too. Tommy on Points for me.
You are making a lot of Farr's height and reach disadvantage here but I think that his style was largley based on conceeding these.