What's typically considered the "cut-off" speed tier for a Trick Room Pokemon? Like, slower than Base 100?, 102, etc?
108 according to some people *cough* DarkMilotic *cough*
But seriously, I'd go with 70ish. The main thing to be worried about is naturally slow stuff "outspeeding" you in Trick Room, like ferrothorn, snorlax, slowbro, etc depending on the tier. Faster stuff gets "outsped" by even base 60s like azu, clefable, etc