Yes, depending on how you score, you might get either a 'meh' or a negative reaction. It doesn't affect the game much though. You still need to go through all 3 routes to get all the CGs... I think.
I mean... The Sayori hug CG you get whatever you do. (Well, not really, but you can get it any route). And you need to play twice to get the CG from your place... But the other 2 per character need to be done by writing poems for the respective girls... so yeah, still need to do the poems 3 times.
EDIT: I think it's possible to flavor one girl without making the others pissed at you. Just pick 2-3 words for the girls you don't chose and the rest for the one you do... should work.