I would get your multi/comm first. Well, it depends on your financial situation, but here's my reasoning.

Hiring *usually* picks up during summer, and we just happen to be about 4 months away from summer. If you can finish your comm multi by that time, then at least you can have your resume out there at various companies.

Once you finish the comm multi, I agree that getting your CFI is a great move, and you can instruct to build time while waiting for a call back on your resumes.

-Imp