I say we table this discussion for now because it's kind of distracting. If you want to make a custom card that is Courser sans Enchantment type, cool. I'd just run Courser for player familiarity, and out cubes would play identically. I am not against the idea of an enchantment subtheme, but I'd want more justification than "it makes courser fit better".
Let's talk about other things:
Hindsight, Enchantment:
Play with the bottom of your library revealed.
Pay
: You may play cards from the bottom of your library until end of turn.
Swamp
When <cardname> enters the battlefield you may sacrifice a creature. If you do, draw a card.
Mountain
When <cardname> enters the battlefield, target creature gets +1/+0 until end of turn.
Plains
When <cardname> enters the battlefield, something something. 1 damage prevention? These should be effects that work at instant and sorcery speed.
Island
When <cardname> enters the battlefield, target creature gains flying until end of turn. Or Scry 1? I have a question of whether these should be combat tricks or just positive benefits that affect you. Should your opponent need to play differently based on what fetchlands you have uncracked? Seems cool. "He has a Polluted Delta open, what should I do?"
Forest
When <cardname> enters the battlefield, do something green. Trample?