My suggestion, which I touched on in the Lifehacker article for Radian
(and based on the same program) (Hi sgtevmckay!):
The ability to launch the program by holding the right mouse button for a second or so. In addition, it would also be nice if one could launch a link simply by releasing the button over the link.
Basically, the behavior is similar to the menu on Neverwinter Nights, which Radian
has emulated fairly well, I think. I initially found CD while looking for something that emulated the NWN menu behavior. I've started using Radian, and I find it far easier to launch than CD. While CD is a more mature program, I find Radian far easier to use in spite of its lack of features, because of how I use my computer.