Done with FFXIV until RDM comes along...

[Duelle]

I'm not really seeing a "gap for RDM to fill".

It's a matter of perspective. To me the gap is "melee DPS that uses a sword". Ignore the debuffer stuff and you could have it as a melee DPS with utility via interrupts, maybe doing something along the lines of MNK and DRG by reducing the mob's resistance to one type of damage (I'd vote magic damage). Design the combat model around a melee and magic mix, and you'd have a real easy time inserting RDM.

This said, I don't think we'll see it until possibly 4.0. God helps us if the devs do something stupid like make RDM the new tank or new healer job they're going to introduce to keep NIN company.