1) Create walkways over and around to keep your cats interested, but also in a way that adds to the overall look of your home or apartment. Here are some more examples:
Even more cat walkways ideas.
2) Multi-Roombas keep Peter's home clean of 15 cats worth of cat hair. Think of what one will do for your home.
3) If you have a closet or a bathroom, install ventilating fans to push the litter smell outside.
But what's missing?
What about an automatic litter box cleaner? What about exercise for your cats?
Unless you're fond of panning for cat turds like old toothless miners used to pan for gold, you might want to look into getting something that will do the job for you. Everything else is automated. Why should you slave over a litter box? Who's in charge here? Why does this feel like work? Ugh. Just automate it.
http://www.catfooddispensersreviews.com/best-8-automatic-cat-litter-box-comparison-chart/ has a nice comparison chart to help you choose between self-cleaning litter boxes. I don't have one to recommend. The only thing I do recommend is to get a bead on the return policy in case your cat(s) won't take to an automated kitty toilet.
Okay, but how does one get a cat to go for a jog? Is that even possible? It is.
Consider a "Cat Wheel" by One Fast Cat. Such a wheel might run around $250+ shipping.