When deciding to upgrade from my Hero 2HDs, I decided to go with the Garmin VIRB Ultra30, which has all the features GoPro just announced for the Hero5 plus integration of sensors (like heart rate, altitude, temperature, speed, power, foot strike, etc.) which can be added as overlays to videos in the VIRB editor.
Also syncs with your mobile phone (via app) for camera control.
The Hero2 HD had an arcane and clunky interface clunky, needed extra packs for poor WiFi, and I wanted more modern cameras with 2.7k and 4k capability.
The only downside, which is temporary, is that accessories are limited for now, but the VIRB Ultra uses the GoPo mount so I can use all my mounts.
Spare batteries are the one thing I miss so far.
Competition drives market innovation once again.