I regret not having enough money for everything i want.
My NAS build is perfect for my need, and i think it’s perfect for most of us, i’m sure there are tons of people that take my suggestion and take some hints from them.
The only real regret i have, is having just 8 GB of ram, for folder caching, 16GB would be better, but i can upgrade, so no problem.
The, of course there is possibility for improve, like ECC, IPMI, better case, bigger drives etc, but those things cost too.
If someone have the capability of troubleshooting and DIY, this remains the best solution for money and performance. Prebuilt are good mostly for company and people that don’t want too many problems.
Do you plan having VMs or only Containers? Because Plex, alla ARR stuff and NVR can work on containers. In that case the i3 is extremely overkill too, but if you plan to run a lot of VMs, the i5 of course have more core.
In terms of power consumption, both idle around 25W (generic system with no GPU and Idling HDD), the i5 would peak more, but depend on the usage, generally server idle 99% of the time.
TDP doesn’t mean Power Consumption for Intel, but is related to Thermal Dissipation. The i3 would consume the same as i5 idling, because of C-state and the ability to almost shut off the unused cores, then on peak power, having more cores and frequency, mean more power consumption, but peak mean burst of 1 second at max.