Former med student who withdrew in first year considerations for mba school

I am a former med student who withdrew in good standing and have been interested in working in investment banking. I applied and was not selected for Equity Research Associate Biotechnology after an assignment. I think I can handle a career like this because I was straight-As in premed sciences and math.

I would like to get into a program right away to improve my career prospects. I don't qualify for a one year mba based on my short tenure at med school without being a degree- holder (I think) but I may be able to get a gmat waiver for a two year mba.

I am trying to decide between mba and law school.
Can you please help me weigh pros and  cons or examine this.

If mba route I thought I would want to go into equity research but is it dull work?

I seem to feel studying law in law school would be A LOT harder than the first year courses in mba school even finance related courses. I have taken since withdrawing from med school a mathematics for management course in which I received an "A".

Most importantly How hard is it to valuate companies, would I get stuck doing financial modeling forever and not advance , if I naively load up on finance courses for my mba will I have a hard time passing, etc? What are the career prospects for an honestly 30s female in equity research trying to make a mid course career correction?

And it's attractive to me to get the test waiver; however, I would still have to take lsat if I were to go that route 

thanks!