Whether Space Marine Devastator Token should see play would depend on the specific metagame and the prevalence of artifact or enchantment-based strategies in the format
Well, for starters, it doesnt restrict you to only green creatures, unlike Green Suns Zenith or Natural Order
This cards seen some Vintage play, where you can ninjutsu it with fast mana after attacking with a 1- or 2-drop
Research current Standard or Alchemy metagames to find tier-one or tier-two decks that suit your playstyle
This green Leyline doesnt often see play as often as the others, especially not in a 100-card singleton format like Commander, but I think its an underrated inclusion in any lifegain deck that can afford to run it
Then the three-drop enchantment makes a 1/1 Soldier with haste on arrival and then when you target just one of your dorks you can make another token and copy this and target the new token