I think once you refine your strategy a bit, the end game crisis should become quite manageable (unless it spawns right inside your empire). I was facerolled in my first two games, but these days I usually have around 300-500k fleet power, and I keep my last ascension perk slot open, just in case.
The Khan, otoh, is rather tricky. I don't think most midgame empires are able to defend against him unless they manage to put a citadel with a decent sized support fleet in his way.
The Khan, otoh, is rather tricky. I don't think most midgame empires are able to defend against him unless they manage to put a citadel with a decent sized support fleet in his way.