He is a four year old miniature show horse and until this year his neck was great, so need ground work advise.....and when it says backing up, how much and how often. Plus I still don't know what a back roll is??
I would go with ground driving for your handsome prince there! It's the same as riding except on the ground of course. But that way you can work on pushing him forward and really getting him to use his hind end, topline, and then of course his neck too.
A rollback.. that's a western thing. It was explained to me but I'm blanking on the exact wording so sorry if I mess this up guys. Something about traveling in one direction and doing kind of a tight you turn to go in the opposite direction?
For backing up, you do a little every so often. Backing up a hill is great work, same with walking up it,, encouraging the horse to stretch his neck down.
How is he doing in side reins? Is he understanding what they're for?
Do a refresher on flexing at the poll so he can do it with ease. Carrot stretching before you work will help to loosen him up. I have a thread about it here: Stretches (and muscle building) for your horse
The ones for riding, you can come up with creative ways to do that on the ground :) Be sure to ask if you need help!
The important thing is not to force the headset.. it'll come naturally when the horse starts carrying itself correctly, regardless of size