I have 2 friends in their 40s who are primary care physicians at Kaiser (one in Bay Area, one in Sacramento). Both have dropped down to 60% time (3 days per week), explaining that 60% time is actually 40 hours. In the last few years Kaiser has added both EHR work and e-medicine work without reducing the number of appointment slots. So, it's about 7 hours per day of appointments and then catching up on all of the deferred paperwork and emails.
I've found a opposite experience. They seemed to like sutter the best, a bunch of others not bad and kaiser was so-so. It might be a case-by-case issue depending on the specialty.
Not true. A primary care physician at Kaiser makes a bit over $200K if they work full time AFAIK. Average American makes about $50K. Considering the 4 years of med school and 3 years of residency they are not overpaid. Specialists are the people making $500K+
Also, while I don't know about the competitiveness of jobs in certain locations, rural states can have some of the higher mean wages for fam and gen practioners (https://www.bls.gov/oes/current/oes291062.htm).