I think you have a good understanding of it. From your name, I'm guessing you're a Parelli fan, so I'd like to say you have endless possibilities with ground driving. You can challenge you and your horse to see what you can do, but after you get the hang of it of course. You can drive him over poles, and sticks, and around obstacles. See if you can get him to go over a tarp. Of course be safe and don't get tangled in the reins.
You could also work on other lateral longing techniques or desensitization since you can't ride. If you need any more ideas just let me know
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