I would love it if Body Slam was made a TM for the first time since Gen 1. It was a favorite of mine back then, as not only the strongest Normal-type move at the time with no negative repercussions, but also as a move with a relatively high chance to inflict paralysis. It has only gotten more useful since, as abilities like Serene Grace, Sheer Force and Pixilate have made it even more of a viable option on various pokemon. It was nice that they made it available in Gen 3 as a one-time tutor move, but it's time for another comeback.
In addition, while I never liked using this move much myself, Rollout DID make for a decent early-game TM in GSC. Used correctly, it is the single most powerful attack in the game, though it is of course extremely rare for it to actually REACH its max power in a battle.