I wasnt talking about struggling to figure out how things work, I was talking about the fact that a complex system takes time to learn the finesses of, and that is a major part of the fun. A simple system that just lets you pick up and play cannot by definition be as rewarding, because there is no challenge or learning curve involved. Its the difference between a dr. Zeus book and the Illiad, really.
But that was part of the problem in Oblivion. Look at it this way. Think back to pen-and-paper RPGs. If there was one thing budding DMs were warned about, it was "rule lawyers" and "min-maxers". I.e., people that were trying to sit down with a calculator and anolyze the game. While I think some people's "it breaks immersion" complaints are way too finicky and
Princess-and-the-pea-ish, there is something to be said for having game mechanics that don't require you to sit and think about them to use them. Oblivion was pretty bad in that regard. For all the complaints about the UI, and the ones about how container-inventory lists are (dis)organized are valid, it is in fact far faster and visually cleaner than Oblivion's, and I spend far less time screwing around with the UI in Skryim than I did in Oblivion.
Similarly, spell creation in Oblivion just wasn't all that and a bag of chips like some people seem to think. I always had (1) a weakness to fire spell, (2) the best ranged and touch fire spells possible at my current level of skill (2) the best self-healing and healing-others spells possible at the time (3) the most potent summons I could get hold of, (4) the best unlock spell possible, (5) a feather spell and (6) a shield spell. All the other spells I came up with, all the fortify spells and the like, they were at best toys. I'd create two spells to fortify speed and athletics by 100 each (usually for like six seconds at most) just so I could ZZZZZOOOOOOOOMMMMM for those six seconds. Or a charm spell to get better prices, so I could accumulate a bunch of money I didn't have any more use for. In short, I just didn't get some huge kick out of spell creation in Oblivion. I think it likely that when I make a mage character in Slkyrim, I'll have just as much fun with the magic as I did with Oblivion's, despite not being able to tinker with the numbers the way I could in Oblivion.