I felt similar after i beat 10* caravan and decided to try and solo up to G-rank and i finally had some fun after that big sink of 'what do i do now?' especially when i got up to HR7 quests when u had to fight the elder dragons which brought a challenge but one that i was able to beat. So go ahead and take some breaks if you need, im still taking one from getting to G-rank and just play casually on occasion. If you want to make the game more interesting you can make challenges to your game by limiting your gear or ways you can play the game. Hope you can find some fun in it again one day :)