Nextcloud is hard to install in manual way (even sometimes with Docker). As far I know, both Snap and Yunohost versions of Nextcloud are solid. I used Snap version on the cheapest Linode VPS, and it worked fine, especially when I doubled the SWAP to 1 GB. Now I use Yunohost version and I have only good time with it. It is super stable, fast and reliable. I used Nextcloud_ynh on HP 800 Mini G3 with i5-6500t and now on Asrock Mini PC with Ryzen 7 5700g. It is working just great.

If you don’t want to use Nextcloud, you ca install Vikunja for kanban and tasks. For notes Hedgedoc can be great.