Your diagram is fine, and a pretty standard "Advanced Home Network" we see around here.
Anything can be made to talk to anything across different VLANs by choosing to allow it on pfSense. If everything on one VLAN needs to talk to a server in another, you should evaluate if that server is in the right VLAN, or does it really belong with the others.
The big problem with VLANs in home environments is that you need to make so many exceptions just to get everything to work like you want. If you're trying to use VLANs as an extra step in security, how much security are you really getting with so many exceptions on pfSense?
Your layout and questions are not at all unusual, I guess I'm just always wondering if VLANs are being pushed too hard onto typical home users who will waste more time trying to tune them than any benefits they actually receive.
You're into tech, so it won't be a problem. I do suspect that you'll become lazy over time and just stick things in the main VLAN with broken promises to "fix it one day" as your personal time diminishes.