To weigh in my own two cents The only reason I would say to read the original over the remake is that the remake isn’t finished yet (still three routes to go) and the original Tsukihime has more influence on the larger Nasuverse since it came out 24 years ago

Imo this is balanced out by TsukiRe just being a better written more fully complete game and story in the two routes it’s remade so far So you cant go wrong by choosing either one