Attacking and making land drops are two of the most fundamental parts of Magic , and being rewarded for simply playing the game is extremely potent
A reasonable option, I think Lay Bare the Heart is mostly a modest upgrade over Transgress the Mind (a decent, not great card itself)
When it comes into play, it taps down all legendary creatures, and it keeps legends from 'readying' in the untap phase, potentially locking them down for the rest of the match
A word of caution on my older posts however
Cards like Void Winnower and Jin-Gitaxias, Progress Tyrant are just a few of the exciting options to drop in with that ability
Turn one, draw a card, play nothing, discard a card in the cleanup step, throw Primeval Spawn into the graveyard, turn two basic swamp, cast Reanimate targeting Primeval Spawn is totally something you I would try do in a game of EDH if the restriction wasnt present