Agreed.
1) But... rebels can still be a major threat to great powers. I'd disagree with k-59 that rebels are a small threat: they only are if you play well/conservatively. If you accumulate lots of war exhaustion (I'm playing PDM, where I think this is a bigger deal...?), rebels can still be a huge problem for #1 GP. As the US, I had to deal with major communist revolutions periodically from 1890-1920 as a result of my hyper-imperialist war exhaustion.
2) Semi-on-topic: rebels should definitely fight each other. It doesn't make sense that white reactionaries and Jacobins cooperate, or that fascists-communists-anarcholiberals do the same. Unless they're nationalists/patriots (I mean, unless you have Hungarian nationalists and Slovak nationalists who aren't fighting for the same territory), they should all be enemies. I also think they should all get their own flags (Jacobins get some sort of tricolor maybe, idk... fascists get a black flag, communists get red-and-black, anlibs get black-and-yellow, nationalists/patriots get a modified flag of their homeland - maybe with a special border or something- whites get a white flag, etc. etc.).