One of the things that has been really missing for me in Skyrim is the lack of any way to upgrade individual spells for mages. Warriors can improve their weapons and armors with smithing but all mages can hope to do is buy new spells. That makes low level spells (like flames and sparks for example) totally useless at higher levels. I enjoy using those sustained spells but trying to use them at level 30 is suicide. Mages feel completely underpowered in Skyrim compared to a warrior or thief type character. I really hope the first DLC addresses this issue.