I'm tired of seeing people on the internet using the word "laughable".

The article was interesting, except part of it stems from the authors thoughts on a resurrection scene. The creators have stated that one character was to die, that they determined his from the start, and later that they had no intention of bringing them back. Now, as to if they were going to kill her at the Northern Cave, they post some interesting points but I doubt it. Her only dialogue is minimal, she should have had some when the group is all united before they head out from the cliff climber's house, or the part where Cloud gives a party member the black materia, they all say something then, I think. The one part that is puzzling is why Aeris' theme is playing. My guess is that it's just the music they gave if someone were to access it from the debug room.

Onto your second question, it's a little weird. At that point she knew Sephiroth was going to have her killed, and Aeris knew it could very possibly be Cloud to do it. She also knew that she had to return to the planet to be able to stop Sephiroth, so she wanted to pick a spot where she could die...somewhere serene. I'm guessing she had never been there, and she chose that as the place.