Maybe it's because I only have about 20 non-Google apps installed, of which are 3 web browsers, 2 are chat apps, 2 CardDAV and CalDAV apps, a better calendar, and Spotify, Netflix, Twitch, and Amazon Video. All Google apps except Maps, YouTube, Calendar, Messages, Camera, and Phone got deactivated. If anything looks like it's using a resource hungry background service it doesn't need, it simply gets uninstalled.
What I did from the beginning to keep the battery in a good shape was to never load over night to 100%. I plug in my phone before showering and eating breakfast in the morning and this loads it up to 90%. But I don't plan my day around charging my phone, even when it sounds like it - when my phone needs charging, I charge it.
One thing I also did, that might impact battery performance: I deactivated animations entirely. They are unnecessary and keep me waiting for things I could do a lot faster. As a side-effect some loading spinners aren't animated anymore and show a static circle shaped arrow but that's okay for me.