This question may have been posed before but why not have daedric light armor?? I'm sure it would be highly sought after and look awesome. Again, if this has been discussed before i apologize.
In Morrowind you could get Daedric hide which the fine people at TR used to create their Daedric leather stuff, though I doubt you'll see anything like that in skyrim.
Okay. Some elements allow for light and heavy armor. Stalhrim for example.
magic ice is lighter than god's blood? i dunno, i'm not agaist light armor or light weight ebony, its probably just a gameplay thing so the styles are more differentiated.