Whichever party is in control loses a lot of seats and that was not exclusive to Obama despite what Sanders Christ Superstar implies. Obama spent just about all political capital on health care when he had a majority in Congress and after that majority was gone there wasn't much left he could do, but he did do something besides be charismatic. There is no model that is going to keep Democrats in power indefinitely because that is not how the electorate works.
But it didn't have to be so terrible either, especially not at the state-level.
There's a reason 2002 managed to actually be favorable, there's a reason 1998 was a stalemate in spite of the scandal, and it wasn't just because of Congress.
The funny thing about the posturing in this thread is that Sanders would have been radioactive* for downballot Dems if he got in office.
*His primary opponent would have been too. So Dems were screwed either way.
True, the best realistic outcome for 2016 was for Trump to win, and the GOP to hold Congress by less. Then Jones would've flipped it.