The skills and so forth isn't what I meant by 'balance'. I should've made it clearer, but I made that last post on my phone whilst I was sitting on the toilet and thus my capacity for verbosity was compromised. The game's balance goes beyond the mathematics of levelling up; things like details have to be balanced, story elements have to be balanced, NPC voices have to be balanced, loot and quest rewards have to be balanced. It all has to be balanced.
Consider this; did you think Black Reach was awesome? Yes, you did, and that's because the awesome has to be balanced. You have to have different types of awesome in the game, and not too much of it, otherwise nothing would stand out; the game has to be filled up with boring (but still pretty) clutter in just the right amounts. If you put too much awesome into the game, it just becomes weird.
The NPC dialogue in the game has been balanced. They've managed to put the bare minimum of unique dialogue into the game but balanced it well enough that it isn't too irritating.
Yes, of course, some aspects of the game are 'broken' in the sense that the right combination of skills and equipment make you a nigh-invulnerable killing machine. You have to put that in an RPG. Hell, for most of us, working out how to break the game is the game. It's possible for a game to be too balanced, which makes it dreadful. If a single-player RPG is too balanced, then all paths of character progression become equal; in which case, there's no point in having any customisation of character progression at all.
This is why I rarely play mods; most mods add new features that unbalance the game. DLCs and add-on packs also have the same effect. Don't get me wrong, mods can be fun, but if you add, say, twenty unrelated mods to the game (not including graphical overhaul mods, bugfixes, UI mods, etc.) you end up with a frankly bizarre game, one that I find it difficult to play. The thing is, you can tolerate a bunch of different disjointed mods because you installed them. If the developer adds twenty or thirty random things to the game just because they're cool, the game doesn't knit together so well and you end up with a profoundly weird title, one that people won't be as bothered to mod.
I don't think people give Skyrim enough credit. In most respects, they learnt and applied a lot of lessons from their previous mistakes, and yet made relatively few new ones. I think the game is balanced in most respects, and all the elements come together well. I'm completely happy with the amount of content in the game. The next game will have a lot to live up to.