All in all it looks like the Red-Greens have lost their chance to become a big party - this time. It will still be crucial if they manage to stay ahead of SPP. If they do I think they will squeeze out SPP in the long run. SPP is the second most redundant party in Danish politics (no prize for guessing who is no. 1) and if the Red-Greens would kick out their Trots/Antifa-sympathizers, drop the rotation rule for MPs, create an actual youth organization (instead of relying on an activist style non-affiliated Socialist Youth Front), run their own list in the Euros (a chance to scoop up left wing Eurosceptics) and elect an actual chairman they could probably kill off SPP in a decade. Of course that is not going to happen, but even a couple of these changes would go a long way.
I see what you did there. Basically, what you say is : if only Red-Greens could become a "serious business" party like SD or Venstre, they would finally be a "serious business" party. Well, maybe they want to renew things a bit and not be a copy of what has always been done.