I think you are in conflict here between your technical issues and your artistic merits. Your questions are fine but your examples are not because of the reason I just mentioned.
No amount of tilt would get everything in focus because of the railings in those bridge pictures. The railings are too close to the camera. It doesn't matter with objects too far like mountains for example.
At 24mm, it really doesn't bother me. Viewed fullscreen, the image is rather pleasing. At 85mm, it's pretty annoying. Both of these images were accepted by Shutterstock, which was my goal (as opposed to satisfying you lot). But I admit I was surprised they took the 85mm shot. Perhaps the reviewer found it interesting, or perhaps all they care about is that a certain percentage of the image is sharp, in which case the tilt served it's purpose. The 24mm shot has sold at least once already, which is always a good sign. I just shot it this past weekend.
Nobody asked me, but I personally think either of these shots would be better using focus stacking. At least in theory. Unfortunately, Nikon hasn't released the bloody SDK yet for my D810, so I can't DO focus stacking, unless I want to do it manually, which I certainly do not.
None of the above is on topic. Whether I'm an idiot or not because of how I choose to use my tilt shift lenses doesn't matter, and frankly it's a highly opinionated topic. Your opinions are different than Shutterstocks, and I care about their opinions more because they're how I intend to make money. Clearly, Shutterstock wants sharper images all the way through too. But if they'll take it and it sells and the customer is happy, that's sufficient.