Nearly there
Keep current. I was looking for a job for about three years. Just so happens I decided to renew my out of date IR and then got a call a few days after for an interview etc.
If I was not up to date, i doubt i would have got it. It was the usual, 'are you available now'.
The MCC will also help if you get a sim ride. CRM and all that stuff.
FI rating is good but not surehow much it helps with getting a RHS job. In my experience, few airlines see it as an advantage.
If you are in the lucky position of not owing any money then don't worry about a few grand to do both.