Xros wars is 100% better than the new adventure, if you have problems with its slowness, its mostly the first arc.
The death general arc is really well defined in my opinion.
The new adventure mostly consist about beating a random villian then slowly advancing onto the other random villian and there isn't really a plot until they reach the "Important Villian" that happens to be just a regular villian in mentality but a bit stronger in power.