a) bold changes are not possible without significant majorities in our Congress and increasingly our Judiciary and obviously a President to sign the bills. Nothing is more important than getting these majorities. Nothing is more important than voting for every candidate with a D next to the name. From Joe Manchin to AOC. If they are a democrat, they should get every left of center person's vote. Full stop.
b) if those majorities exist, then I support bold change (even if it gets you voted out of office, i.e. Obamacare)
c) if they don't exist, then I support incremental change
d) if they are in the minority, I support keeping what we've gained as much as possible
The repukes are only changing things for the worse, so I agree with point a) and d) wholeheartedly.
On b), Obamacare is typical of an incremental approach, which often leads to what us French call a "gas plant policy" on account of gas plants complexity. I think a similar US expression is "spaghetti ball".
c) sounds absurd to me. If you don't have a majority you can't do anything.
The deeper issue is: Nobody who gets excited to vote for incrementalists. Baby steps don't inspire anyone. So in order to get a strong majority you need a well thought and bold platform. Neither a "tiny baby steps" platform nor a totally utopian platform will get you votes. You need to balance ambition and realism in order to get elected in the first place...
The guy who was elected in 2016 was not an incrementalist.