I have been in your shoes, currently at the end of suspensory rehab. I found there’s only so much you can do in the saddle walking straight lines in terms of your own fitness and strength, and that things out of the saddle (bodyweight workouts, stretching routines, pilates) are sort of where it’s at in the meantime.
As far as keeping your rides interesting, I used the opportunity when it was purely 45 minutes of walking in straight lines to get really, really, really good at our halt-walk transitions, and transitions in the walk itself. Extended walk, slow as possible, medium to the next tree you see along the pasture. Halt walk, halt walk. Coincidentally my mare HATES standing still so this was the perfect time to work on this. Lots of backing to keep her stifles engaged.
Work on straightness, picking out objects (or patches of grass or leaves) to walk towards and keep your horse between your legs.
Focus on each area of your body, identifying stiffness or tension and then figuring out what needs work. I found being forced to JUST walk allowed me to work on things that I’d never slowed down enough to consider, and in terms of your horse’s fitness and response to aids, this COULD be very productive time. Boring as all hell, but productive. Wish I’d had a pasture for mine. I’m sick of the ring but we weren’t allowed to leave even ground.
I am thinking you are an evil person down deep?
