Just got back from a remote area in Kenya where we deployed a subset of RACHEL content on two computers/servers. A Windows 10 laptop and an old 2006 Mac Mini with a new SSD, both running Apache 2.4 webserver. The computers were connected by ethernet to a router with WiFi and an additional AP was also connect to the router by ethernet.
Students accessed the server using their choice of AP (they had different SSIDs) The idea is that if they are getting poor performance from one, they can try the other. In experience, we had 36 tablets connected and response time was not an issue. Browsing was a mixture of web pages, and videos.
I don’t have experience with either the RACHEL-Pi or RACHEL-Plus, but redeploying the Mac Mini and letting the laptop serve as both a Secretary laptop and webserver seems to be a good low-cost solution for this location. I will continue to monitor the operation and report more later.