Big 4 to MBB? Master or MBA?

Hi everyone, I really need an advice because I’m feeling quite lost…

I am working at a big4 consulting firm(not strategy) and I’m not completely satisfied with where I am, I think I can do more impactful projects which are quite rare here. I’d ideally work at an MBB firm, but I don’t have enough qualifications for it (B.Sc with average grades and 2years of big 4 experience) - hence not even really worth trying.

I am thinking of how I can increase my chances do become more competitive on the job market, here are a few options:

1) wait for 1 year, become a senior associate and apply for an associate position at MBB (still very unlikely to get it)

2) Apply for a top masters program and if I get it put my big 4 job on hold - this will open up many opportunities

3) Wait for 1-2 years, become a Senior Associate and do an MBA - again, better job opportunities

I know it’s not perfect, but it bugs me that I “only” have an undergraduate degree. Have you been in a similar position? Please share your thoughts, what next step would you take if you were in my position?

P.S I have full respect for professionals with and undergrad, I just didn’t do so well in mine and need a second chance :)

Thank you!!