Welcome,

I too reside in the US but have maintained AC E for years. As others have stated, it's really what you want to get out of it.
For me, I fly UA for business, but my personal travels take me to Canada or Europe. I'm always able to use my certs for upgrades. I don't mind sitting in E. To be honest, most of the road warriors at SMF are Premier Exec or Ik, so the chances as a Premier getting upgrades on an airbus are slim to none. The most I would make on UA is Premier. I will often pay out of pocket for E+ if not successful in asking, and enjoy using the RCC. This has come handy when stuck in ORD. I actually run into another road warrior who lives in the US and is AC SE. We've had this discussion many times about switching and he has maintained his status with AC and has been SE for years.

Evaluate what you want/need out of your travels.