Mass Storage Device - Opinions

Please NEVER use exFAT. Especially for storagenode. See

If your disk is slow - it’s more like SMR, see PSA: Beware of HDD manufacturers submarining SMR technology in HDD's without any public mention
Avoid use SMR for storagenode.

Regarding filesystem - it’s better to use a native filesystem for your OS. If you use Windows - use NTFS, Linux - ext4, OSX - APFS.
Mixes will have problems sooner or later, leading to data lose/corruption and disqualification.