@TMathis 

You do not say it, but it appears to me that you have VLANs defined on the switches and use the ‘router-on-a-stick’ topology. There is nothing that would prevent you from using the same topology to connect more than one switch to the router. However you do not really want to do it unless you have no better option. If you do that traffic in the same VLAN but on different switches will flow through the router, too. This will make your local network lot more dependent on the Internet router and potentially make the router lot more busy. It also appears to me that you do not really use the SFP slots on your switches. So, why not to use them to connect the switches together in order to free up a couple of RJ45 ports. If your switches are located close to each other, you can use inexpensive DAC cables for that instead of fiber.

  @TMathis 

I am a heavy NAS user so it is very important to me to have my network as much as possible independent of the Internet router. I find myself rebooting that router more often than any switch and don’t want my backups, surveillance camera recording or viewing, and accessing my NAS in general be affected by those reboots.

I understanding your determination to free up as many RJ45 ports as possible, but daisy-chaining switches is usually not a desirable topology. Also, be careful with that ‘ring’ configuration since that creates a loop. Such loops can make a network inoperative rather fast if STP/RSTP is not enabled. I would rather connect the TL-SG2210MP switches together using SFP and connect the switch in the middle to the router using its RJ45 port. Using SFP transceivers increases latency. Since you are not concerned about your network being independent of the Internet router, I would connect the TL-SG1008 switch directly to the router. I would just make sure that only low traffic devices are connected to that switch. I do not use an Omada controller, but to my knowledge it would be fine to connect it directly to the router, too. However I think the best place for it would be the switch the APs are connected to due to its role in the WiFi mesh.