the second of the long drama is much more serious than the 1st season. Now that our heroine has decided who she wants to be with, of course there is a lot of political plots and plans amongst the palace. The 2nd half of the 2nd season is much more serious and seems to bring into light what we see a lot of in past historical dramas. ie: scarlet heart.
You also get to see a lot more interaction of prince 4. I ended up skipping parts because some of them got very repetitive.
Overall, i would watch it if you have time, but if not, its a skip.