You are too pessimistic. In my opinion Pelosi is just slightly worse than Ryan.
There will be no impeachment. Trump will find common ground with the democrats on a massive infrastructure program and they will get along fine.
Meanwhile, the Senate will keep confirming judges (and a new attorney general with balls).
Good point. The biggest reason the U.S. didn’t get a single-payer system under ObamaCare is that Pelosi is owned by the insurance industry. She’s going to have enough trouble dealing with the growing lunatic fringe in her own party.