That is not an answer I would be happy about. The video module then is worthy only for Amiga 2000 because A3000 already have high-quality scandoubler with flickerfixer. Pity he does not plan AGA module 
On the other hand, the digital signal will (presumably) provide better output quality, so still some use for the A3000 with your LCD (and no issues switching between RTG and "native" modes).
BTW, quite a few of the old-school scandoublers (the A1200 DCE one comes to mind) weren't 24-bit. Not to mention, a considerable share of LCDs out there aren't, either. (An
example of one of the techniques some manufacturers use to "fake" greater color depth...)
