Follow-up to : "Help Needed!"

So I thought it would be time to do a follow-up to my previous post: " Help needed! I'm sure I've doing something wrong in Rising Star for 15 months, can't figure out what it is.", and I think I still need help.

Currently I'm at level 53 and about 27.000 starbits. But I'm still stuck on the acoustic tent level. I've been doing that level for over 6 months now.

I did buy some more boosters and have increased there. But it still seems like it's going very slow.

There are a couple of good cards, such as:
Vintage Road Bike

How do you play the game and is there anything you are doing that I should be thinking of?