I personally played WoW because I felt it had the best lore, and most engaging character balance. Everything progressed “logically.” Of all the MMO’s, and I’ve played them all, it just seemed “smarter” somehow. Ironic considering other games had more options technically with alternate advancement and whatnot, plus it was probably the most “cartoony” of them all!
The problem trying to reinvent classes from MMO titles in Elder Scrolls games, is that a large component of class balance simply has no direct correlative in a single player environment.
As Keldrath points out, debuffing is a major part of that. In a multiplayer environment, developers can plan abilities of certain classes which “synergize” with abilities of other classes, because you can pretty much count on having some class in your party that will help you maximize it.
So, creating archetypal characters in Skyrim comes down to three major elements or strategies, being RP, simulation, and content recreation. Topics like this always get me thinking of the last option there, being the Creation Kit will be released soon.
For example, how would one reinvent the function of totems? Perhaps some sort of effigy involving elementally charged soul gems (where different things you trap have different elemental properties. So, certain materials one collects combined with certain “sagas” or “songs” the player has learned will enable you to create a certain type of effigy which resonates elemental energy to some effect.
The quicksand idea has merit, though I’ll be the first to admit I svck at animation and particle effects!
The idea of familiars also comes to mind. Flock of crows, that blind your enemies!
“Tentacle snakes” are always fun! Like the dark energy arms of entropic mojo sapping certain skills. But then that’s more like necro-shaman, and that sort of thing is all in the visual spell effect.

One really cool idea Age of Conan introduced was heal over time effects based on 2-handed attacks. Bear shaman really were a fun class indeed!
EQ if I remember correctly made good use of wards. That's one thing I really want to see in a mod. Instant cast wards with a duration.