Ki exercises, what a great suggestion. And breathing, you don't even have to move any furniture!
The not imposing on your family made me think of another warning...avoid the temptation to use a wife rather than an imaginary uke, unless she volunteers (even then, you might just use this interest as a way to get her to join class). Most of us, at one time or another, have enticed a friend or spouse to 'grab me here'---most reactions to having a technique applied to them by a beginner when the friend/wife doesn't know ukemi has not been favorable. One girlfriend of mine whould grab my wrist and say OUCH OUCH OUCH at the same time. 'I haven't done anything yet," I'd protest. "Yeah, but you're going to and I don't want you to" she'd reply.