Belated reply...
I started writing up some material for down the eastern coast of Africa using sections of the Periplus that was leftover from Between Sand and Sea that wasn't workable for the Egypt book...
Once Upon the Erythraean Sea | My Life as a Grog (Boats)
Languages of East Africa | My Life as a Grog (Languages)
The Comoros Islands are particularly interesting as they were visited by King Solomon and have an indigenous jinn tradition - technically they are below the equator though so in Mythic Europe terms they would potentially have to be beyond the Ring of Fire or in a region or similar...
Oh and Mythic Hind is technically Faerie - David wouldn't let us use China (Serica) or India (al-Hind) as "real" places due to the medieval paradigm so basically the further east you go everything breaks down into Faerie or Magic - I wrote "the Silk Road" section of tCatC and everything goes all "soft places" after you cross the Pamir into the Tarim basin or the Indus