Needs diversity...
WHile I liked Plymouth I think a good Solar System tale needs a diverse setting, like the Moons of Jupiter or Saturn. Short travel times and sufficiently different locales for good yarn spinning. Of course travel times can be mere days system-wide if there are high gee fusion drives around - or Jordan Mcclay's Vacuum energy rocket. Or even quicker with a wormhole network like in Baxter's "Timelike Infinity" or "Cowboy Bebop" as someone has mentioned.
Hmmm... a Niven-esque setting with Earth vs Belters, in a semi-friendly rivalry kind of way. Have the fusion ships launched off Earth with a Space-Elevator/Rotovator?
Adam