Replenish has been closing games outright since day one, and even in the present Modern metagame, Resurgent Belief has shown how powerful mass-reanimating enchantments can be
Either way, the Storm payoff that Ral offers is really difficult to access
They give a storefront for customers to view your inventory and provide a system for creating and managing your collection
Youre more likely to see a value hold on, say, Eternal Witness (which can port into most green decks) than a high-powered green commander (which can only really be used as the commander in one specific deck)
You get to take advantage of staying alive via lifegain synergies, and you can use edict effects to keep opponents in check
Appealing designs are a major point of attraction for any TCG, giving cards an intrinsic artistic value to complement their efficacy in-game