Requests Tier? (Patreon)

Yo, I'd like to see what you guys think;

I've been wanting to get better at sketching and doing line stuff since my lines are terrible, so I've been thinking of adding a "Request Tier" for people who want to pay extra for a monthly refined sketch.
This tier would have 2 or 3 spots, not sure yet. I don't want it to overwhelm me either (My workflow is kinda slow).
This tier would also have all the benefits from the other tiers.

Not sure if I would keep it or not if I do add it, but trying it out wouldn't hurt.

This also means that I would have to change my Patreon's monthly payment to Up-Front payment rather than every 1st of every month, though to be honest I should've probably switched it a while ago.