Very true. My first playthrough I don't remember it, but my Electric Monotype I recently did came down to the wire. It wasn't bad in my Dark Monotype though, because I had a Persian with Fur Coat and Screech along with a Torracat rocking a Z-Move.
The person below me has traded to get a post-game only Pok?mon that's in the region's Pok?dex and use it before beating the game (i.e. Leafeon/Glaceon or fossils in B2W2, Riolu in Sun/Moon, etcetera, NOT to be confused with National Dex stuff).