but I think that needs a common Data store (probably will be using the NAS for this)

Note that this setup could be a single point of failure. For true HA, you might want to consider deploying two storage boxes with replication (SAN or NAS), or configure a hyper-converged infrastructure using solutions like VMware VSAN, Ceph, or StarWind VSAN.

Encryption is key for securing your data. Utilize tools such as VeraCrypt and Cryptomator for robust file encryption prior to uploading them to cloud storage. Alternatively, consider using virtual tapes, as implemented by Starwind VTL. In this caseour data remains unaccessible to cloud providers.

A powerful AI model.

Zabbix. Aslo for Windows, it could be Rainmeter https://www.rainmeter.net/ or HWiNFO https://www.hwinfo.com/. For Linux, Conky.