Any looming theoretical limits to the length of a cable stayed span ?
Compression in the deck near the towers springs to mind, but just add more concrete, no ?
(like in the typical precast deck segments typical used, but instead of them being identical the length of the bridge, progressively thicken the walls of the segments near the towers.
As for wind loading, similar effects on much longer (true) suspension bridges have been dealt with.
As for vulnerability of the span to wind prior to completion, how the heck do they deal with that now? Seems like a deal killer for several already built, so there must be something they due to moderate the risk.