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Monster houses aren't even present until the second half of the game, and by the time you get to them, you should have a room-clearing move.
Butterfree has compoundeyes and Silver Wind, so it has a room-clearing move that never misses and will boost it up to max stats on a single use in a monster house. It's also easy to recruit and gets useful IQ skills like Map Surveyor and Multitalent. Alternatively, anything with a room-wide move and the Concentrator IQ skill can do the same thing, although grinding IQ is pretty tedious until late-game. Plenty of other mons can link Defog/Sweet Scent/Lock On/Mindreader with a room-clearing move.
Monster Houses are not a problem unless you're playing blind, but even then after the first one you should figure it out.