Hey question,
Why don't you do anymore DYI videos?
to make a long story short....
looking into building a wireless router with and i5(its just here collecting dust with a bunch of other cpus) and then while doing some research i learn bout ALIX boards, maybe you're more knowledgeable than me, and i need more info.
Its better to just use a router designed to be a router. I have run internet through custom built routers, servers and more but have found that there is a significant dent in speed and latency. Its fun to do but is far from practacle. Huge power consumption (Especialy when you use a server as a router like i did) in comparison to a standard netgear router, no real major benifits and huge dents in performance. I wouldnt bother.
Repurpose some of those old computers into servers for your network. Hell, even setup a lab