If your salary would be about the same, then you are stronger staying in a small firm, getting a promotion (hopefully more leadership experience), and salary growth on record (all those things are important).
P.S. Keep in mind that your pre-MBA work history is important, however, since you will be relying on it to get jobs, interviews, internships, so you don't want to look at it only in the perspective of admissions (too immediate). In this light, a big4 would be an advantage but having a promotion/higher standing would be as strong esp if you are staying in that industry.
PPS. really cool GMAT score!
_________________
Founder of GMAT Club
GMAT Day is Coming! - Awesome way to turbocharge your GMAT Prep with expert panels, breakout rooms, free prep resources, and Prizes!
Just starting out with GMAT?
Start here with a Study Plan... WAMC! - What Are My Chances - Automated Profile Evaluation Tool is Here!
New! My Ultimate GMAT Focus Score Calculator