I started to go down the Unifi route, but the low speed and limitation of the USG stopped me. I ended up buying an EdgeRouter-4 to replace some of the duties that USG and I bought an Intel NUC with 4 Intel Gb NICs and installed OPNsense to handle all of the firewall duties. I use the ER-4 for routing, VLANs, DHCP, and Netflow reporting.
You don’t necessarily need to split firewalling and routing between two devices like I did. I was aiming more for a configuration one might see in a large corporate network. This provides an opportunity for me to learn more about routing and network automation with Python. I will eventually script most/all of my network configuration. I may even try to use Ansible for network automation.
Network segmentation will not only provide better stability for your use case, it’s also a great way to provide security within your network (once you start blocking traffic that does not need to traverse both networks). This is only the beginning. As you learn more you may decide to create a VLAN specifically for IoT devices so that they can talk to the internet and nothing else. That is the beauty of VLANs, their easy to create and control network traffic.
Good luck with your lab.