It sounds like you're going to want to adapt the following HOWTO for a couple of different VLANs & AP/SSIDs assigned to different radios. I would suggest looking at the Flint v2 (GL-MT6000) however. The HOWTO will still work & the Flint v2 is fully supported by 'pure'/'vanilla' OpenWrt if/when you find yourself needing to go beyond the limitations of a SOHO-style 'appliance' approach to networking.