You know I've never had a problem with the animations in TES games :S They've always looked fine for a free-roam FPS-RPG of their generation to me...
I mean, when people judge Morrowind and Oblivion's graphics now they forget they were practically the Crysis of their times, a torturous ring of fire to put your computer through to prove your fealty to the gods of gaming...the retailers where I first got the game were *warning* everybody who bought the PC version that their computer probably would die a horrible fps-lag death trying to play it.
Oblivion was no Crysis of its time. In fact, Crysis came out a year later and ran much better than Oblivion. As well as UT3 and STALKER. Not to mention earlier titles like Doom 3, Butcher Bay or Half-Life 2. Morrowind was sort of impressive in its time with the water reflections and bump mapping, but Oblivion? Not really.
I know it's a fallacy but I can't help presuming that if spellmaking isn't in the game itself Bethesda'll have no reason to be restrictive about the extent of spell effect modding. Having said that, given that the emphasis is on "unique" spell effects this time (as opposed to, say, fire/frost/shock being exactly the same thing bar different projectile handling) it's probably more likely to go the other way, with modders having no control whatsoever over stock spell effects (excepting perhaps a few variables for quick balancing).
Bethesda's modding support ain't about restricting access to things, it's about giving access to the things the content developers use in a more accessible form. If all the spells are pre-made, then chances are the spells are hard-coded, with no accessible way of changing them.
Also, good job twisting a clearly negative change into something "positive", guys. Going by the philosophy of "if it's imbalanced, remove it instead of balancing it" is never a good thing.