I think you'll see a lot more of him when primary season is over. He'll go all out to avoid dealing with or responding to Trump tho, and rightly so.I agree. Do think if he loses in 2020 the new AG will pursue obstruction charges.
Regarding Obama, I go back and forth on whether his (frankly superhuman) restraint is a good or bad thing. Part of me thinks he should be out there regularly talking about what’s going on, since he’s still comfortably the biggest unifying figure for Democrats - lets be clear, if he could have run vs Trump in 2016 he would have won roughly 57 states