Maybe not the right answer for you since I am not VPS-based but basement-rack-based.

I would choose Debian + docker for whatever available. Just make sure you have enough space for those. And probably even enough CPU.

To me it makes sense to separate them but some would argue otherwise with Docker/podman/container. Remember, Docker however by default is root.

The one I would actually do at home is Docker on a unpriviledged LXC (Proxmox) to make sure that there is no real root processes running

Cheers