Man, that brings back some memories! I used to have that same table. Anyhow, I've found that dust collection on a router table is problematic when you are doing pattern routing without a fence... cuz there's no good way to collect it, without putting something pretty close to the bit, which can really be obtrusive when routing many type of pattern shapes. However, when using a fence, I get darned near 100% collection through the table by using a dust port on the bottom of a box that encloses the router. It's very much like what you have except my router is buried in my table saw's side extension and the box is something I made from plywood to enclose the router and collect the dust.

What makes this work is a ramp I have in the back of the box that encourages dust to flow toward the front where the port is, and the port is right at the bottom of the box where it can be most effective. I used a short piece of pvc, which is just the right size for a standard 2" flexible dust hose. I attach that to my normal 4" dust hose with a plastic adapter.