It is more the case of whether the card disadvantage is worth the effect when you are not screwed or flooded, which the depth of filtering with a nice range of costs and the synergy of Looting with so many effects ensure is the case
The Rattleclaw Mystic will flip up for two to make three and then tap for those colors too on a mana dork two flip and drop 2/1 body
Plus, it comes back to your hand when it dies, skirting around commander tax
The ability to bounce any permanent allows decks to cover their bases, gives you the option to position things early or in a waiting game by bouncing a land and it makes sure that you'll get to trigger the discard effect
Going back, though, there's a noted dearth of interesting legends from this era that I'd love to see remedied and to have some get their time in the sun
And if you dont need that extra boost in mana, The Prismatic Bridge can just put a creature or planeswalker from your deck into play during each of your upkeeps for free