Funny question, if Zouken back when he was young, extremely good-looking, in love and wanting of world peace were to pop up, how would the family react?
Well, I think Sakura would be forgiving in that case, and Kiyoshi probably would be too, since he never knew Zouken personally. Shirou and Rider would be a lot more wary, though, especially Rider.
I have empty slots and I'm currently weighing my options, one of which is Good-Looking Young Zouken. Another is Also-Good-Looking Old Zouken, but I have a fairly good idea of how they'd react.
Yeah, old Zouken would be terminated with
extreme prejudice if they got anywhere near any of Sakura's family. Well, except Rider, who would make sure to capture him and hold him prisoner so she could torture him mercilessly for a
very long time....
I'd say option one and then make Zouken the loving type of Grandfather, the kind that gives hugs and is mostly cheerful. It is a surefire way to weird out of The Emiya Family and maybe even temporarily break Sakura's mind.
It wouldn't break Sakura's mind, she's capable of accepting that Zouken wasn't always an amoral collection of penis worms.
I also wanna pit [Mike's] Sakura and Seras against each other at one point, which should be an interesting fight. They both use shadows in different ways, Seras has a arm that is pretty much a living vampiric shadow which she can manipulate at will in a fight
Any reason they'd fight, though? Sakura doesn't go out seeking battles and Seras doesn't seem like a villain.
Yeah, beat up the guy who hasn't done anything yet, and who at this point is an all-around cool guy out to protect his waifu.
He gets worse guys, sure, but while he's young he's chill. He has a goal to make the world a better place, and has friends, that nice Tohsaka guy and his waifu that never loved him back.
Also he has a different name. Might be only Sakura would recognize him.
Hmm, well, if he's already started to transform himself into a worm man they'd be a little wary. At very least I think they'd tell him what he would become if he continued on that path.