Very weak theory. You include stuff, that isn't even true, and it's just grasping for straws, which makes the entire theory worse. Tobirama and Minato do not look similar in any way...
If you had compared him to Jiraya, maybe that would go better, but not Minato.
Different eye color, different hair color, the hair style is not similar in any way except for spikes, but Sasuke has spikes too, does that make it legit to state Minato is an Uchiha?
It had been more spot on, if you made the comparison to Tsunade. Having similar jutsu means nothing, because they didn't know each other anyway, Tobirama died before Minato was born.
Also the last part, which you call the strongest evidence... There is no saying, that Minato couldn't have a senju as mother, which could make the whole thing legit, however, the metaphors you are grasping for can be interpreted in several ways. IMO Obito is simply saying as he is, because he is mentioning the symbols on the feud between senju and uchiha, and Sasuke and Naruto are quite similar to Madara and Hashirama.
They also began as friends, then they were enemies, but ended up as friends again. And lastly they ended as enemies. The same is probably gonna happen again.