I think it is worth keeping in mind, that TNSR is more intended to function as a high performance router than a firewall, and as such I don't think you should necessarily use that instead of pfsense/opnsense/vyos/etc.
It all really depends on your application.
Generally speaking, I suggest you scale the performance of your firewall to the bandwidth of your internet connection, if you need/want a high performance router (such as a L3 switch) to move traffic on your internal network, I suggest using a device that is separate from your firewall.