If you can't go over you can make mazes, L shapes, weave lanes, all will keep him supple and thinking about where he's moving his feet. I also like to teach a full / side pass along poles too, but that might be too much for him just yet.
In the walk work you have below - all of which sounds great btw

don't forget halt / walk / halt transitions and if you are allowed rein back and 1/4 / 1/2 pirouettes too
This is all something Bally will be doing an awful lot of if and when she's allowed back to work, so keep us posted on your progress

I will, I can't wait to go and ride Amigo today! Honestly, there is so much fun stuff to do at walk, I could happily do walk work for ages and ages. And I find it so relaxing and low key overall.
Let's hope it's a *when* and not *if* for Bally. You would have to do a blog of her comeback to work, as everyone would be so happy for you both.