vLANs on router + unmanaged switch vs a managed switch for small home network

A little bit of background -- I don't have a large amount of network-connected devices in the one-bedroom apartment I share with one other resident, but they are increasing. As such, my network needs are currently met with an ASUS RT-AC68P running AdvancedTomato.

We've got a desktop computer wired straight to the router with full access, a wired printer on a LAN-only VLAN (that is accessible from the main LAN but not the reverse), a movie player (wired), chromecast and tv (wireless) on a separate internet-connected VLAN. At any given time we have between 2-4 phones and the same number of laptops connected to the main LAN's WiFi. In the future I'm planning to build a NAS/home server to connect to the main LAN and will probably grab an ethernet adapter for the chromecast. DNS is handled by a pi-hole VM on the desktop, as is my NextCloud server and a couple game servers (all will be offloaded to home server when I finally build one).

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Basically I foresee needing a switch in the future, for the home server, maybe another desktop, chromecast ethernet, etc. Assigning vLANS through the router and giving them each a small, unmanaged switch seems to be the simplest solution, but this leaves few available ports left on the router should we acquire another desktop (the other half has seemed interested lately...) or have other needs, and (may) be more expensive.

A managed switch then seems like it would be the more versatile solution, but are there downsides to creating vLANs on the switch vs on the router? If I recreated the vLANs on the switch, how do I configure access to the internet, to other vLANs, etc? Is this all done through management on the switch or will it be more involved (i.e. creating routing rules on the router)? What would y'all do in this situation?

Thanks in advance for any input.