STEM background to IB

Hey guys, fairly new here just wanted your insights on this.
My background: Indian kid currently in my final year of BTech in Biotechnology ( ~3.6 CGPA). Strong academics in high school with a lot of extracurricular's (national champ in a sport- don't know if this would be relevant or of any value). I've decided to switch my trade and enter into IB although I know it'll be a gruesome process. Have a research publication and strong internships (healthcare/biotech sector) under my belt and had straight A's till +2 and undergrad in mathematics. My knowledge of finance is solely based on some books ( IB: by Joshua Rosenbaum
Joshua Pearl, International financial management by Cheol Eun) and a course on quantitative analysis and financial modeling (UPenn course on coursera).
Recently I've been selected for an internship/training program in IB captial markets through which I'm expected to land a role at JPM, Citi, GS, CS etc.
Current plan: Gain xp >> grad school ( undecided between MFin & MBA abroad) >> IB
So I have a few questions:
Given my background what would be better MBA/MFin?
Would an internship/job position in capital markets of an investment bank be helpful further on?
How much weight do courses like above carry while applying to grad school?
Job prospectives in Europe/UK in IB for international students?