Actually, the GL used to have a time-fused firing mode, but it added a lot of UI clutter, and was rarely useful (VERY useful sometimes though). It got removed as a design decision, so I doubt it will be coming back. The GL did get a range buff as compensation though, which was probably a good deal for PHALANX, on balance. I'd rather it got a high-register fire option over timed-fused fire though, personally.
I suppose a case might be made for bringing back time-fusing as an ammo option, but then you are bringing back a different type of complexity for small gains. I suppose the code for time-fusing still exists though - maybe there is a mod with it in?