Migrate Fortilink vlans down to switch

Background: Currently our environment is FG300E --> FS1024D --> SW448(10)   All VLANs are configured on the single 1gig fortilink port on the 300E. Initially this was fine because traffic never really peaked above 1gig but I did not realize this meant all traffic was passing through the fortigate. I incorrectly assumed the layer-3 FS1024 was doing the intervlan routing. Oops. We are implementing an iSCSI SAN that will have traffic routed across VLANs and 1gig is obviously going to be a huge issue. What is the best way to (for lack of a better word) convert or migrate some of the VLANs to static routes on the switch? I am aware this means I will lose the ability to have security policies between VLANs.