Tough decision.
When I finished training, I got a right seat turbine job. Now I am in the position where I can't upgrade because I don't have the PIC time. In retrospect, I somewhat wish that instructed a bit after training in order to get some pic time.
With that said, don't instruct simply for the pic time. Only do it if you think you will enjoy it.
Also, there are many jobs out there right now.
If money is an issue and you can only do one, I would go with the MIFR.
However, I also think it will be easier for you to find an instructing job than anything else.
Basically, do what works best for you. Thousands of people have done the instructor rating, and thousands have found other jobs...in the end, it always seems to work out.
Good luck!