Right now, it looks like the plan is to purchase an older Mirage for around $400k, in 2020. Meanwhile, I'll get time in some Complex/HP rentals to build time. The Mirage will meet all her criteria, and get us a few hundred nm in a couple hours. If she takes to traveling more by air with THAT plane, then, (assuming financials hold) we'll look at stepping up to a new M600, or dropping a bunch of money in upgrading the Mirage. I'm hoping to stay with the Mirage for the long haul, and trick it out to our tastes. I like the idea that it won't be too much plane for the more common short hops that we have more often.
Surprisingly, now that I've gotten my Instrument Rating, she seems more relaxed and enjoys flying a bit more. She likes how much more structured and precise IFR flying is. (Or at least, that's how she perceives it.)
Thanks for all the replies.