The one problem with this is that it puts a 2-handed warrior at a severe disadvantage. They'd either have to put away their 2-hander in favor of a 1-hander and a torch or resort to spells that might go against their characters. Unless Beth were to introduce a third option, like the wearable lanterns mod, but that kind of renders torches obsolete.
They could include large "light aqueducts" that could be lit with a torch and would light up the surrounding area (sorta like in the movie National Treasure, among others). This could illuminate the darkest areas at the expense of alerting nearby enemies and removing sneaking's viability for the time being.
I wouldn't mind the occasional dark dungeon, but if it's done in a way that it punishes players for not being Khajiit or a Vampire I take issue with it. Pitch black dungeons shouldn't be the norm is what I'm trying to say.