I have a few ideas for you:
1. An animation,
2. Clicker deck,
3. Survival simulator,
4. A deck dedicated to your favourite character,
5. Mukbang(s),
6. Very detailed remake of other games (for example, the ending kit),
7. Find the [item or thing] Game,
8. Rng based game,
9. Ragdoll deck(s),
10. A sandbox game,
11. Drawing or deck contest (Requires you to have a great amount of bricks though as a prize for the winners),
12. Cooking deck,
13. An idle simulator,
14. Start or take part in a remix party,
15. Take care of [character] simulator,
16. Destroy the [item or thing] game
That's all I could think of, and thank you for your attention.