I actually think that signing Falcom is fairly plausible, at least moreso than other Japanese publishers considering the pc market there is practically nonexistent and there's still a pretty big stigma about DD. I mean it's gotten to the point where they pretty much have to drop out of PC market (and focus on handhelds/phone stuff it looks like) because their distributor threw in the towel, so I wonder if they ever considered switching to a DD platform. After all I remember hearing that Recettear sold more on Steam than it did in Japan (although that's probably not hard nor is it as comparable since that was a doujin game).
Falcom seem pretty interested in expanding their fanbase in the west, what with their partnership with XSEED on their Ys and the Legend of Heroes PSP games and plans to release Legend of Heroes and Sorcerian for mobile phones in the english market (independent of XSEED's work on LoH for good or ill, probably the latter).
And they worked pretty closely with XSEED too. First time they did translation work in house too, IIRC, since they did all the work inserting the text that XSEED translated into the games themselves (instead of in the past where the localization programming and text insertion were done by whoever licensed it like Konami or Atlus). Not to mention that the script for the official Oath in Felghana PSP release was based off of the ill omened PC version patched that got shipwrecked in some awful shitstorm of internet drama, which they licensed to increase the turnaround time. Something to keep in mind since Tom of XSEED is a huge Falcom fan that I think he also worked on the recently released Ys 6 PC, Ys Origin, and Xanadu Next fan translations in his spare time.
I don't know if there's any legalese in the contracts with XSEED that prevents it or if they could get all the fans that worked on the patches to cooperate, though.