I know it could be situational but if you had to pick only 1 enchant to use on your gear, which one would you pick?
another “best (game thing here)” question… 
There is no best of anything, it’s all based on what you prefer. Although right now the only enchants that will do any good for you are power and defense enchants.
By far, power
power vastly outstrips all the other enchants rn
hard as a close runner up
Sorry for being unoriginal, i’m looking to see how others feel about some of the current features in the game and didn’t see this sorta question pop up yet (maybe there is idk yet).
power and hard are the best enchants as of now. all the other enchants are made to scale off of the 5000 max or whatever, so they are kind of underwhelming right now.
agility doesnt even do anything at all
In my opinion, Hard and Strong are the best enchants
Since I’m a Moonlight user, I’d have Swift enchantments on all my gear to maximize Magic Speed. That way, my light magic will be virtually unavoidable. Pair that with Wizard Armor & you’ve got a big storm coming 
seeing as none of them have actually shown a difference in stats besides hard and strong, i would choose to use hard seeing as my magma already does a good amount of damage and having all that extra health would have no major downside
Without a doubt power