@Techrantula are your switches L3 capable of inter-vlan routing? I'm using USW-Pro-MAX-24-POE with 8x 2.5G ports and USW-Pro-Aggregation with 28x 10G ports, both are L3 switches. So I have plenty of ports to do LACP link aggregation and the switches can offload hardware routing to give my UDM-SE a break. I created bond0 (2x2.5G) and bond1(2x10G) in PVE networking then use VLAN tagging to separate out the different networks (Management, corosync, VMnet, CEPH public/private). Bonding the interfaces will allow for redundancy and greater bandwidth. At least that's my plan. I haven't gotten free time to setup CEPH yet so don't know if my networking setup will work. So far done iperf testing they all communicate just fine.
I think your plan will work just fine too. Just create different VLANs to keep each of those networks separate you should be OK. The PVE recommended networking is a bit overkill of homelabbers like you and like. Separate switches for each networks will get crazy complex and expensive. I think if you have L3 switches and setup VLANs for each networks, that should be OK as you're not pushing a ton of traffic like in enterprise environment.