I have the 13" MBP since September - I have experienced 1 KP related to BridgeOS during sleep (with older macOS, it hasn't appeared with 10.14.2). I can trigger BridgeOS KP when I run disk utility check on the system drive (live checking). I'll sent report to Apple directly via dev bug reporting system, not only via the system dialog if 10.13.3 does not resolve it though. I have no keyboard or audio issues.
The fans: In my experience it idles at 0 RMP without external display. With the display connected it usually won't turn off the fans entirely, it rather keeps them running at ~800-1200 RPM (not audible).