Yep, disabling face unlock makes notifications show up again on lock screen1. I have no issues with notifications showing on the lock screen, are you using face unlock? It's been know that face unlock code in AOSP has issues and QPR1 is expected to fix most issues when it's released
2. I've had 5G in the statusbar previously, haven't tested recently because I'm not in a 5G area. Already looking into it