Well, that I see no issue with. Being universally trained in Perception is already the "they have heightened senses" thing. If the idea is "Elves are creatures of the light and embrace the daylight and fill their homes with soft, bright glimmering magick" then by all means, they shouldn't be able to see in the dark and shouldn't have dark vision.
What I was more trying to get at was that the idea of dark vision is pretty simple. Its basically just "you can see in darkness as though you were carrying a bright light source even if you aren't carrying a bright light source". Its not exact, but its basically that simple. It references a rule you are already going to be using anyway. And I feel in a lot of games the exact distance tends to be ignored since rooms are rarely larger than 60' in areas that are going to be completely dark anyway.
What I don't really see a good reason for is to create a separate set of more complicated rules for when it is dark but not complete dark and have to quantify exactly how dark is too dark and have a special vision mode just for that which is going to apply exclusively to Elves. That seem silly.
But if you aren't creating that separate set of wishy-washy gray area rules that require the DM to calculate the phase of the moon and the general humidity conditions for that particular region due to its proximity to large bodies of water and mountains in order to calculate the weather forecast all to determine if the Elf can see and instead you just want to pull Dark Vision off of non-subterranean elves, it seems fine to me. They still have better vision than anyone else not trained in perception.