My Series 3 has been randomly rebooting throughout the day (https://forums.macrumors.com/threads/series-3-rebooting-after-watchos-7.2255209/) <--- like this through all the betas. I was dismayed when GM still had the bug present. Full resets and setting up fresh or anything of the like isn't helping. Anyone in the same boat on 7.1? I'll go beta again just to get stability back. Would have loved to have gotten stability back with GM, but here we are....
For anyone experiencing poor battery life after installing Watch OS 7, I was having the same issue until I performed an unpair with reset and repaired with my iPhone. Now getting excellent battery life again.
If that was right after installing the update, keep in mind that the Watch (along with iPhones) take some time to reminded a lot of stuff after installing a new OS. Check it again after some days have passed (many install an update and then check performance immediately afterwards, and see it lower, and blame the new version of the OS for being slower).