Thalia and The Gitrog Monster are great since they give you additional land drops and slow opponents down, while Tayam, Luminous Enigma is a powerful value and combo engine in the command zone
Because it turns out that in practice, Regrowth isn't used primarily on creatures at all
If you recall, Rampant Growth is a card that was deemed a little too powerful for Standard formats, which is why we actually get Sami's Curiosity instead, ensuring that if you draw it a turn too late, you'll have to pay the price for it
I would definitely give it points for being inventive, for sure
While this cards abilities would be outclassed with far superior Zombie lords down the line (Lord of the Undead from Planeshift, Undead Warchief from Scourge , Death Baron from Shards of Alara , among many others)
Goblin Charbelcher deals damage equal to the number of nonland cards revealed this way to any target