I moved from Nextcloudpi some time back & found THIS TUTORIAL far & away the most useful. Instead of just saying copy/paste a Docker Compose file he shows how to build it step by step using Portainer so i found it invaluable for future projects.
It seems a bit overwhelming initially but once you’ve installed it a few times you’ll be able to do it from scratch in less than an hour. Probably less as it sounds like you already know what’s what having used Ansible
Never knew I needed? Another vote for Paperless-ngx. I still feel like I’m living in the future using it. The trick I’ve found was initially setting up a good document naming & management convention & following it religiously for every document. The search function is fantastic at narrowing down results. Used in conjunction with specific coloured tags I can immediately see what I need from search results.
Fired up Immich recently. Amazing. Will be donating as I like their stance.
I also enjoy Linkwarden. Switched from the also excellent Hoarder as I prefer the UI.
Most used? Nextcloud with Joplin.