Have you considered getting a cyclocross or sport touring bike and throwing some bikepacking bags on it? You dislike the lack of nimbleness that results from the especially long wheelbases of heavy touring bikes, it would be more than durable enough for a 30lb load on the road, it would satisfy your weight-weenieness much better than anything else you're looking at (including stuff like the 920), and you'd be looking at a far larger selection of bikes that come stock with the kinds of shifters and wheels you want.
Seems like the only question would be whether the gearing is low enough. CX bikes often have doubles bottoming out in the realm of 35 gear inches. (And this can be dealt with if you're willing to replace a few components.)