If this is actually an alternate version of the Kerbalverse (instead of our real universe), then you can relax on making your universe possible and just follow basic Kepler orbits while putting in whatever you like. It's already known that Vall and Bop get ejected from the Jool system in a matter of a few years in n-body simulations, so even the official one is quite impossible.
Plus, the 1/10 scale makes interplanetary and even interstellar travel MUCH quicker and easier. But then again, most Kerbals don't seem to mind being strapped in a Mk1 Command Pod for centuries, either...