From what I've seen, D&D is content to use the most basic of "real-world" sciences, and leave the rest behind. This holds true from microcosms of DNA to macrocosms such as space.
This is an interesting idea. I like it. That way one doesn't have to come up with crazy alternative models for things like falling.
I can't remember if it was Aristotle or Ptolemy who said that our world was surrounded by a large crystal shell, which is what we saw at night...but that became the basis for Spelljammer.
It is Aristotle who originally articulated this. Ptolemy just created the mathematical models for it.
Likewise, Darwinism isn't out-and-out said to be untrue, but most races, such as elves, orcs, dwarves, etc., all hold that they were brought into being in the image of their deity/deities. Humans, for the most part, seem to hold vaguely true to this also, although there are still examples of more primitive humans about, but nothing that'd be called truly sub-human.
That's my take too.
For issues such as a shocking sword underwater, I'd modify that to be that electric attacks underwater are like fireballs...they take effect as a sphere that damages everyone in, say, a 30' radius or so with electric damage. Likewise, fire attacks can't be used underwater, etc. Beyond that, simple is best.
Given your other statements, I'm surprised you're taking this position. There's nothing in Aristotelian natural philosophy to explain electricity behaving like that and modern explanation of electricity is all about electrons.