The BMCC sensor is just slightly larger than the Pocket camera, to get the 2.5K, compared to the 1.9/2K resolution of the Pocket/Micro S16 sensor. They both share a close close IQ, with the BMCC giving a little bit better fine detail resolution due to the slightly larger sensor.
If you want to keep the Pocket camera compact size, and S16 IQ look, but add a bigger monitor and improved mic preamps with XLR connections, look at the Micro Studio camera paired with the new Video Assist 4K monitor/recorder. Use the VA to record the image from the camera (ProRes or DNx only, no Raw) with sync'd improved audio. If you want Raw p, yiumcan record Raw in camera, and ProRes proxy with the audio track in the VA, and line them up in Resolve or another NLE to syn'd the VA audio track with the raw camera recording. Also, the Micro camera has better audio suport /preamps, and yiumcan get good sounding audio from it, when you use a good preamp and mic.
The advs together of going to the Micro Cinema camera is a faster sensor readout time, so you get 1080p60, or Raw at 60fps, and better controlled alaising/RS shutter artifacts. Or just get the BMCC, but you still are going to need a good mic preamp with the BMCC, it has the same audio issues as the Pocket camera.