When we had this discussion in Riombara, I believe it was said that Grehk actually was the first capital of Riombara, but after Rio was destroyed it was refounded in Athol Margos. Both cities thus make sense.
According to Rio's wiki page, it started out in Rines. Grehk belonged to a whole lot of different realms before Rio took it.
In any case, the most central cities are also *very* valid capital candidates RP-wise.
And with what I've suggested, only Fwuvoghor and Melegra would suffer extra penalties. In any case, Rio can't seriously believe it will hold Fwuvoghor forever with its capital in Grehk. The last attack was botched due to poor Enweilian movement and TMP, but there's otherwise no way Rio can defend that city from so far away against the west's full force. I therefore would not see any unfair prejudice, as 1) they have valid cities that are central, 2) these cities have historical reasons to support them, and 3) the only regions it would hurt are regions that are doomed because of travel times anyways.
Rio wasn't what I was thinking of when I suggested this, but the case applies pretty well.
