They already changed Dragonmark lore once during 4e where any race could get any mark, though certain races had a higher percentage of certain marks. Further, the Mark of Finding already has two races that it can manifest on (human and half-orc). I can see a possibility that the dragonmarks become level 1 feats and the Houses aren't necessarily racial but bound by whoever has a mark. In that, an orc could get the mark of Finding, an elf the mark of Detection, or a human the mark of storms. It will be a deviation to the lore (And Micah will hate it) but I think they will do it again to accommodate the new species paradigm.
Then again, my Nostradamus ratio is pretty terrible, so who knows?