For fanless Poe ruckus makes the 7150c12 which should have plenty of power for your needs. Tplink has an 8-port Poe fanless option as well as well as a few others but ideally you want 802.11at (Poe+, up to 30W per port) . I saw one on eBay for around 225 usd (used)
Unleashed is just an AP that runs the controller (a "zone director light" of sorts). It's quite handy but if you already have the ZD then you don't need it.
The AP below is the H510 that can be mounted flush over an wall box and gives you 4 local ports)
(If you go for the H series don't buy the H500 as it's end of life. But there are a few H510 on eBay for around 100 usd. )
The r series can be laid flat but will send signal "up" which is not the ideal direction. It's not meant to be a tabletop model although for a single room it will be more than enough.
Right now, on eBay, you can find r500 aps for around 60 usd which is a steal to be honest. Those APs also have 1 passthrough port so you don't lose the jack you already have.
You can keep two switches so you get a smaller Poe and keep your 24port non Poe.
Poe is pretty much plug and play unless your cabling is a complete disaster.
Good luck!