I like lawnchair a lot. Not having news/AI crap constantly loading is defenitaly a plus for battarty.
There's some knockoff/divided forks, here's the version I use.
https://github.com/LawnchairLauncher/lawnchair
Additionally, NetGaurd is great for locking down what has internet/cell access. It uses VPN, so if you already use that it won't work, for only 1 VPN can run at a time.