I don't believe we're ready to go to another continent yet. Tamriel is full of interesting people, places, lore, environments...heck, many of its provinces have yet to really be touched upon in any way shape or form just yet. Everybody thought Morrowind was a volcanic wasteland filled with mean-spirited Dunmer, and then TES3 came along and whole new insights were given into their culture and customs. I could understand if we'd be up to TES VII or so, but you're really overexaggerating. There's plenty more to do with Tamriel. I would suggest you expand your lore horizons - and experience more than one game in the series.
One has to consider that Oblivion took concepts such as skooma, annoying Bosmer, Akavir, and blew them tremendously out of proportion - in my opinion, they were far too prevalent in Oblivion and have really made their significance (or lack thereof) very unrealistic. Just because Oblivion has to hint at Akavir every other second (to hide its own inadequacies concerning Cyrodiil no doubt), doesn't mean that it's such a cool place to visit. Sure, we have so little information Bethesda could really dazzle us, but it's kind of like the Imperial City. Fans had their own depictions of its grandeur, and then Bethesda gave their "canon" version and it was nowhere near as impressive as we had hoped. I'm not saying this always happens, but it's quite possible.
To leave Tamriel is to draw focus away from the primary races and their own conflicts. The "settlers in an untamed land" concept worked with Morrowind because you were expanding off of the pre-existing Dunmer. It'd be neat to learn about the inhabitants of Akavir, but in the end this would be for naught as this is not the primary focus of the series. Maybe in another decade or so a
Redguard-esque spinoff could be done, but I would rather keep the primary installments of the series here on Tamriel.
Take Myst for example. They make four games, write a couple books, all supporting and building of the legend of the D'ni civilization. Then they make a terrible a game where you can go into a lame city not at all like how it should've been.
Riven and the books of Ti'ana and Atrus made major contributions to the lore and helped keep the story of Atrus and the ages fresh and interesting. I'm hoping as Bethesda branches out their franchise (such as over these novels) we'll be able to further elaborate on and explore Tamriel, instead of having to wait 4-year periods for new lore. That's the biggest problem for a series as monumental as
The Elder Scrolls - there's too much left unanswered, and too much time spent waiting to learn more. But I still believe Tamriel is a very interesting continent and we don't have to bother with the others just yet.
That is to say, shame to see Cyan killing itself over Uru (though I was part of the original Live "prologue" testing back in 2003/2004 or so and loved the interaction).