I think the ability should cost 
quanta, seeing as the drawing ability is usually time's MO.
And it makes some sense, I guess. I mean, it could kinda be like taking the TIME to worship the tree of LIFE will yield great rewards.
Mono-card draw in other elements shouldn't be an issue as long as there's some kind of drawback that justifies the theme (for example, SoBravery demonstrates recklessness by letting your opponent draw and potential negate your tempo, and Mindgate 'imitates' drawing from the opponent's deck). Time, IMHO, should be best for getting straightfoward card draw with no disadvantages since it has no problem with controlling the future (your draws), whereas other elements need to deal with a condition to get the same results.
As is, I was thinking that tree holds the essence of pure 
and that its variant of card draw is more like accelerated growth than worship.
But what is your drawback?
I mean, with Mindgate, there's not a huge chance you'll draw a card from them that you can use.
With SoBr, you accelerate your draws possibly faster than you can afford, AND you draw for your opponent.
This is just a 'draw a creature' card. It's really cheap, too. I think the hp should go up to 5, and every time you use the ability, it loses 1 hp.
