It sounds like you do need the functionality of a managed switch. I recently went through this myself. I'm not a professional network engineer but I do understand networking reasonably well. I can help translate what the pros here are saying because I'm not one of these guys .. they know their stuff.
What might help this discussion is to understand your needs a bit more clearly.
How many VLANs do you anticipate?
How many clients/ports do you need to support per VLAN?
How are you running pfSense? Is it a Netgate appliance, home built, in a VM?