I get the feeling that the standout candidates this cycle are the ones who aren't realigning their message to match the way their district is thought to lean. This seems... fairly normal. The Republicans love making a huge deal about Nancy Pelosi, for instance. And that gives Dem candidates who want to display some centrism and "I'm not of the establishment" credentials and easy out. Say you won't support her for Speaker, and you get all the benefits without any actual negative consequence unless the Dems win by only a narrow margin. Then, sure, you'll be faced with the choice of bucking the party machine in a close vote, but that a way easier problem to have than not getting elected in the first place.

Same with "standing up to Trump", on the Republican end. Its such an easy and toothless way to position yourself as someone somewhat palatable to Independents and the stray Democrat who might consider voting Republican this election.

I think the more interesting candidates are the ones who buck this trend, and either espouse very conservative policies and trumpet their support for Trump in blue-leaning districts/states, or are promoting very progressive agendas in Red ones.

Depending on the outcome, you can bet that these are the people who will loudly tout how their experience and success is a call for a national strategy along similar lines.

Both sides would be wrong, of course, but everyone loves a simple story stripped of nuance, so come November 7th, you'll either be hearing how supporting Trump to the hilt is the best playbook for 2020, or that going whole hog on a very progressive agenda is.