I have similarly evolved my setup, initially a couple of 'midsize' towers and a StoreVault NAS, then the computers were replaced with a couple of Shuttle XPC type 'box' computers, then the NAS was replaced with a much quieter FreeNAS box from iXSystems, then the 'services' system (DNS, NTP, LDAP, Nagios, etc) was replaced with a couple of small ARM machines (initially Raspberry Pis but migrated to Odroids for performance reasons). And then the last XPC was swapped out for a fanless 'third height' ITX type system that is designed for home entertainment systems.

Realistically all of this could be built into a single hybrid of disk shelf and blade server box. That is something I've contemplated as the 'next generation' of the technology.