Whenever people ask for router OS (VM or physical) I'd always recommend OpenWrt. Come with WebUI by default (unlike Vyos) and you can do advanced CLI configuration with familiar Linux utils (unlike *sense), and for most users you really just want to do some VLAN so it is perfectly suitable. A bonus is that you could use the same UI for your router and AP, so even easier
Generally you will know when your demand is beyond OpenWrt's capability (usually when you can't find the required package in opkg), and by then you probably know the answer to this question better.