I don’t think so. Granted I’ve only played France, Germany (prussia), Russia, and The US. Theres plenty to do.
Most of them have unique journal entries and things they work toward but that could be derailed by other GPs, major powers or even minors. You have enough weight to throw around, but the other great powers will not let you just get away with it. Especially if you colonize Africa or Ocenaia. Most of the GPs have unique journal entries to add to this. America has several about settling the west and the Indian Removal. France has the Royal Pretenders and Algeria. Russia and GB just got stuff for the Great Game.
Additionally, the top spot is rare to maintain. In my longest playthrough as France, it was swapping between me and the UK every couple of months.
Theres also what kind of nation you want to become. While some of the GP are somewhat liberal they do have a decent amount of room to change. The major political movements such Communism, Anarchism, Positivism, Fascism, Integralism, all offer unique forms of government and interesting rp/alt hist scenarios.
Finally, if you really find them bland, there are always mods to add in flavor, new options, etc. I highly suggest Morgenröte which adds new culture based events, journal entries, and even a whole section about recruiting artists and scientists (who themselves could become political agents). Another popular one is Hail Colombia! which adds a ton of America related flavor.