People do tend to reroll their account, yeah. If you're going to do a pull at the beginning, absolutely go with one of the 10-medal deals (currently they're the 358/2 Days ones, and for a single pull they're all basically identical, but I'd recommend either the Xion or Axel deal.) The "Daily Deal" doesn't guarantee anything, so you'll still get rubbish Tier 2 medals from it, and the Small Deal is even worse. Whereas right now the 10-medal deals are guaranteeing all medals are at least Tier 3.

You ideally want both pre-orbed medals (orb = yellow dot) to be damage-dealers, not primarily buff/debuff/healing medals. But you do also want some buff/debuff/healing medals, and especially Illustrated Kairi or Pooh & Piglet would be incredible. Don't lose your sanity rerolling, though. Once you get something decent, no shame in sticking with it.

Also, the permanent avatar boards that cost jewels are significantly discounted right now- 3000 jewels for all of them, instead of the usual 9000. Those are basically necessary to have in the long run because they increase your keyblade cost capacity (a limited resource that caps at 183), so definitely pick those up by January 12th.

The movement just is something you get used to, I think... There's definitely a "pattern" to maneuvering yourself how you want, and in general fine movement control isn't very important anyway. Occasionally there'll be an obnoxious event quest that has you dodging fast-moving enemies or squeezing through narrow gaps, and those are the only times you have to really understand the movement / enemy hitboxes. But yeah, the movement's not the most satisfying.