Note - I do consider what I say below to be a failing of the game not a failing of people to pick up on things. They need to do a better job introducing these guilds that any reasonable person would expect to be anologs of their Oblivion and Morrowind counterparts - rather than what they really are - either the tattered remains of those formerly empire-wide powers or regional counterparts that partly fill the void they left. That people expect them to be and are let down is not because they aren't paying attention, its because they've played those previous games.
I think its easy to miss that most of the guilds aren't supposed to be (or at least not start out as) anologs to their Oblivion counterparts. They have crumbled and fallen far along with the Empire and much of their quests come after obtaining leadership. I think this difference should have perhaps been made more clear though - because a lot of people miss some of that content or don't bother with it because the "main guild plotlines" do feel far too much like they're suppsosed to be the main point by comparison.
Dude, the guilds in this game are a complete and epic fail of empty vacuum. The mages guild hall is devoid of any activity and doesn't even have any ... like.. facilities there. The mages just sit in their bunks and do nothing all day. The questline doesn't have anything to do with magic at all. They need a warrior, and you happen to be a good one, so you need to step up and save their asses.
It's not "the mages' guild." It's a college of mages - and pointedly not any sort of controlling authority on magic in the province let alone the entire empire like the actual mages' guild was. The mastery quests for each of the schools of magic (including getting to unlock the full abilities of the atronach forge), the experiment to recreate the conditions that caused the disappearence of the dwarves, and most of the 21 unique quests ( only counting repeatable quests as one - this is more than the total of all Oblivion mages' guild quests) do have quite a decent bit to do with magic.
Nothing. None of the quests or guilds have any substance or effect at all. None of them have anything to do with their own subject matter. It's absolutely the most hollow collection of questlines I've ever completed.
Well I'll point to the theives' giuld as a counter example. Not only did it feature 24 unique quests compared to Oblivion's 14, it starts as a shadow of its former self and after gaining control and completing 4 specific post-leadership quests you can build it back up to the influencial organization it used to be.
Its sort of how all of Skyrim is - many more factions (each hold for example) and a more fractured world. The monolithic organisations such as the mages' guild and fighters' guild are not here and the college and companions are not meant to be whole anologs to them. They are foils to those past institutions and demonstrate how the empire-wide organisations of the past have been replaced by fractious and often dysfunctional local organisations that fill the void they left.
They definately should have paced them better and emphasized the post-leadership aspects where they were lacking (companions in particular) and made them more obviously present where they were simply missed (most people miss most of the college of mages quests.)