OP, I understand what you are trying to say, but I think you were expecting the wrong things from the sandstorm event in Dry Top. It was not designed to be a dynamic/random weather system; it was designed as a cyclical mechanic of the zone, to stimulate participation in map events.
It would be neat if the open world had an unpredictable weather system, with varying degrees of precipitation, wind, etc., but Dry Top was not an attempt to address this desire. The fact that you wanted sandstorms, and the fact that Dry Top has a sandstorm-themed event cycle, is a coincidence. I think it works really well, as long as you take it for what it is.
I do agree somewhat about the timed nature of the aspect powers, though. After the magnificently-designed Labyrinthine Cliffs, it feels a little cheap to have those abilities kept on a leash. It reminds me of how in the old Mario games, if you got a special power, you could keep it forever, as long as you didn’t get hit or change into something else. But then in Super Mario 64, the special powers were always on a short timer, which guaranteed you could only use them in specific places. I understand Dry Top isn’t intended to be another Labyrinthine Cliffs, but I have to wonder if the time limitation on the aspect abilities is needed.
It’s also really jarring to be fighting an enemy while the zone transitions into a different phase, and have the monster disappear right before your eyes. Really?? That’s actually pretty sloppy.