The thing is this is a Tokiomi at age 18. He is not the head of the Tohsaka family yet, and although is getting close he is not yet in the archetypical magus mind set.
Then, surely, meeting his own family will change him quite a bit, just like how Rin's path was changed by the Grail War (in all three routes).
Also he is kinda smug. It somewhat comes with being the only child of a magus family. Honestly he is like Rin without the tsundere part of her. He will probably convince himself that these people are crazy and try to ignore them.
It's kind-of difficult for him to ignore the fact that Rin and one of Sakura's daughters uses Tohsaka magecraft and that Rin has the crest, though.
Also I doubt anything you say will actually set him of the path of the magus he as chosen.
Probably not, but if
canon Tokiomi had known what would happen to Sakura I don't think he'd have sent her to Zouken.
He will be so much fun.
Lol, possibly.
(i.e., Rider and Shirou would force him to promise at sword/nail point never to hand his daughter over to Zouken...).
Which would make Rider and Matou Sakura pop out of existence because they are paradoxes.
Nope, for the same reason as Ryoko (Rin and Dark Archer's daughter) showing up in her own past doesn't cause her to not exist. It's a different universe, nothing they do will affect their own existence.
