If I had the funding, duckie, you bet your sweet internet ass I would. I wonder that there's not more quality DS development of RPGs in particular, but yeah. I've considered actually bugging 5th Cell - local very excellent DS developer - but the sort of background expectations they have for designers working on handhelds is very different from those in console or PC work. I'm not holding it outside the realm of possibility, though. They've got a great group there, and they do really shiny stuff instead of the shovelware shit of way too many DS dev studios out there.
Also, since you need to fuss with new engines and dev kits and whatnot, and lots of companies shoot for larger, more ambitious projects, you're far more likely to find a standard console/PC developer doing a smaller title for Live or PSN than DS or PSP, which are mainly, as said, done by specialty houses (like Ready at Dawn). The fact that BioWare did Sonic Chronicles was startling for that break from the usual tradition, as well as WTF SONIC RPG WHAAAAT and so on.
Anyhow. MOAR PHANTASIE! Why is a minotaur not in this playthrough yet? They're so good at mashing things.