Congrats on your admits
raghav800! Very interesting situation with you SO going to Booth.
I think this depends on how likely you feel you will be able to get the MBB's and if you feel one shot is enough vs. 2 shots with a summer internship. You have Deloitte on your resume so that should grab their attention enough and hopefully you have M, B, and B, and if you feel that's good enough, sure Kellogg 1Y program is great....
Reasons not to do it is that you will have to somehow manage Evanston vs. Chicago and likely live in Evanston and commute to Booth for your SO or you both live in DT Chicago and you commute to Evanston and he/she to Booth. Also, Booth gives you 2 shots at MBB and summer internship which is safer but a longer round about way if you can get it done.
I would think and wonder what you would your preference be - e.g. would you go to Booth if you got 60K or would that be not enough with opportunity cost/etc? If not enough, I Booth will be unlikely to match that...
P.S. Sorry, I was out on the weekend, so was not checking my notifications.