I like an awful lot about Q'barra, although I think the developers always saw it as a fringe region that they never quite knew what to do with (someone correct me if I'm wrong and there's a big module or novel or whatever that develops it further.) A sub-tropical frontier region settled by Cyrans who left Cyre about the time of the start of the Last War, and who were disgusted by the actions of the Five Nations throughout the Last War, foreswearing allegiance to any of them, is kinda cool. But this change means that they've drifted culturally a fair bit from the remnant Cyrans; think of the differences between Americans and Australians, for example. Politically, they are even more estranged because of the Last War, however. Q'barra is a mix of this population, a steady trickle for a century of criminals, refugees, malcontents, or just those who wanted to get away looking for more freedom, combined with an even bigger influx following the war, especially of Cyran refugees, is a pretty interesting set-up.
I will point out that my take on lizardmen is a little different than D&D's lizard"folk" and in fact is probably more similar to that of Warhammer. I do have two size morphs, but I'm not going to try and match that to large and small lizardfolk or kobolds or anything; all lizardmen tribes have both morphs among them. Snakemen and their medusa rulers are also more common here than in Droaam even, and other monsters such as tropical thurses (skunk apes), ratmen and more all have enclaves of some sort or another deep in the forests, swamps and jungles.
I don't have chromatic dragons in Eberron Remixed, but there is still a dragon in Haka'torvhak. He doesn't really need daemonic corruption, because dragons are monsters pure and simple in Dark Fantasy X, but I do like making them almost more like the dragons of the Iron Kingdoms than like D&D exactly. And, of course, the influx of spies from Riedra use Q'barra as a beachhead into Khorvaire—although that's specifically hinted at a fair bit in print, I'll note that they are more noted for streaming out of Q'barra rather than simply being in Q'barra.
Q'barra population remixed
Human: 38%
Lizardman: 32%
Snakemen: 18%
Jann: 7%
Other: 5%