It allows you to evolve Grass Pokmon the turn they are played or your first turn, meaning you can get a Yanmega up as soon as turn one
Options that are potentially at this time include increasing game speed, seeing enemy cards, revealing the top cards of your deck and the opponent deck, damage boosts, health boosts and more
21/130 Beedrill
While I'm not sure that just Release to the Wind is enough to make the strategy viable, it's possible we get some more blink / flicker support in Dominaria , which would go a long way toward making the plan legitimate in Standard
As elf tribal commander decks tend to be heavily creature focused, some of the strongest ways to constantly maintain a solid amount of cards in the hand of an elf player are through the cards Beast Whisperer and Guardian Project
If you want a more devious way to build Kelsien, slap on him a Thornbite Staff, which lets you untap Kelsien each time a creature goes to the graveyard