I rather like Roseville. There are several fairly nice limited service hotels in Roseville. I've personally stayed at the Courtyard (they have two in Roseville) and Hyatt Place. Other than that, maybe Thunder Valley Hotel and Casino. Not sure if a casino fits your plans, but it's pretty nice and can be affordable on weeknights if you can lay off the gambling.
I worked in the Sacramento area for a bit over half a year and would sometimes go to Roseville. They have a pretty nice shopping mall. There are carpool lanes during the commute hours, so that will help a bit. Traffic isn't really all that bad during the commute hours unless there's an accident.
If you would rather stay near I-5, then maybe Woodland. I've stayed in a few places in Woodland, although it's mostly motels. The Best Western Shadow Inn is maybe one of the nicer motels I've stayed in. It's clean, well maintained, updated regularly, and safe. Some of the other motels in town get poor ratings because of unsavory clientele. However, that's typical of any inexpensive lodging.
The hotels get more expensive as you get closer to Sacramento, and some of the locations might not be that safe. There are plenty of hotels and motels in the area though. I frankly wouldn't stay anyplace close to I-5 in Sacramento except for the area around Old Sac.