Trading in 3 mana (2 to activate and the opportunity cost of tapping Fountainport for colorless) and a token for one card isnt the most efficient sac-for-card trade that there is, but youre paying a tax for the modality of all the other abilities and the fact that its a land, not a creature or something
The proliferate ability doesnt come up as often, but you can set up incredible blowouts, exploit planeswalkers, or discard something to reanimate later
Chris Rahn certainly made sure to showcase one of his best work ever with this menacing (and very blood red) depiction of Elesh Norn controlling the once-good Nissa to do her bidding
Self-damage triggers have been seen in Gruul Commander colors before with Vrondiss, Rage of Ancients and serve as Ixalans dinosaurs signature mechanic enrage but Wayta allows you to safely and reliably activate the effect
To make Moonmist a strong card, you need to be transforming multiple creatures