Check out XCP-ng. Open source, enterprise grade bare metal hypervisor.
I moved from ESXi to it about a year ago, it's been solid. Lots of documentation and support from the community. Lawrence Systems has a ton of great videos on configuring it, both simple and advanced.
For general system stats, I like btop. It runs in the terminal, so you can monitor it through SSH remotely. It also is much more readable than some of the other older top process monitors.
Docker desktop is a nice GUI interface for local docker container management, Portainer if you want something more enterprise grade.