I would not want to miss schnapps and pkgupdate, perhaps also netmetr, from TOS.
Maybe you want to try TOS4.x albeit currently just alpha. The Foris installation wizard provides 3 different installation modes, a bare bones one and then the router are 2 leaner ones. The router setup looks good to me.
However, my trials ended with Various (driver) issues and in particular PPPoE not working stopped me for testing/exploring further.
But the SFP port seems to be working.