In my vision (I use both zooms and fixed UW), there is a difference.
It just seems like you sacrifice some of the final touches of a great photo for some zoom flexibility...
Like, I look at the 1st pic and wonder what I or you would-could have done with a 10.5mm in such a rich enviroment. And even as the macro is much better than the WA, I also feel sad that you didn't have the capability of one 105mm or even a 60mm (though this one would have more problaility of frightening it).
But of course, is a little like on land. You can portrait the same thing with different lenses... The wreck I add last page, I have a plan of diving it with a 18-35 or my 24-85 to register the stuff she has inside, details of the living organisms on the hull etc.