New Nas Build to replace a 7 Year old PC as NAS

I've currently a second NAS wich run on a Asus P8Z77WS Mainboard, currently 7 Years old, i think its now time to replace ( Hardware still running but thinking about energy consumption and lifecycle).
So i'm evaluating a newer Build:
- Mainboard: Asus PRIME H370-PLUS ( https://www.asus.com/Motherboa…H370-PLUS/specifications/ )
- CPU Core i3-8100 3.6 GHz
- RAM DDR4-RAM 2666 MHz 1x 16 GB
- Maindisk for OS: SSD 860 EVO M.2 2280 250 GB
- Case and Powersupply ( where used from another Build )
- Main usage: to start off with 3x 6TB as storage for some PC's as a sharing plattform, also as a media server, maybe some video en/decoding and finally to run some docker or VM's

I know, maybe this plattform configuration is a little bit oversized for my use cases, but i'ts more efficent than the 7 year old hardware and if the system lives same longtime as the old, then the money is not the problem. What do you think about it ? Are there any better or affordable builds which offer the same performance ?

Mainly i will use it as a file and media server, doing some video en/decoding and maybe run some vm's with virtualbox or some dockers.