i just finished the quest line... does anyone feel extremely disappointed by it? the ending just felt rushed and i swear there were about 6 missions?
its a shame because i really liked the Mages Guild in oblivion

Do some of the side quests as well. Especially Arniels Endvour(Something along the lines)
And you will see a very special weapon you might remember from Morrowind....

The main questline for the College is a let down. Too short, too predictable (who didn't think that obnoxious high elf wasn't going to be up to something awful?), and as Arch Mage almost no one in the game even acknowledges this. I really enjoyed all the guild quests better in Oblivion and Morrowind. They took longer and felt like you were accomplishing something special/important.

I find that a lot of the endings for questlines are mildly disappointing in the respect that there's little to no acknowledgement from any main characters (but guards always know what's going on, weird!). After beating the mage guild's scenario I go to whiterun, where the jarl's court mage still suggests I join the college. WTF, I run the college [censored]! Besides that, I didn't get anything uniquely useful to me, even the archmage robes are a let down since I have to sacrifice my armor rating entirely to use them, and all the spell books I found along the way were spells I learned ages ago. If there were more spells to find and earn, and perhaps some unique spells gained from completing this I would have been more satisfied.

"You want to learn about magic? You should visit the college in Winterhold."

Screw that! I didn't learn [censored]! I taught them how to not be dumbasses, if anything.

you think the questline is disappointing? wait until you start going after master level spells. you talk to the respective mage for the ritual (master) spell you'd like to go after, faralda for destruction for example. she hands you a book which is some ridiculously obscure bunch of nonsense and you're supposed to just figure it out. i don't honestly know how anyone could follow through on the destruction ritual spell quest without resorting to the use of a walkthrough.

The only real advantage I can see to having access to the College of Winterhold is that most of the advanced magic trainers are collected there.

I agree with much of this. You'd think the Arch-mage would have more cool stuff in his hizzle. A secret door with some awesome shizzle? I do like having the enchanting and alchemy tables in "my" room, but other than that... meh.

Predictable evil dude was a let down. Did anyone try to kill him earlier just for fun? I was going to. I'll be he can't die because he's important. Weak.

I actually didn't mind the College's main questline at all.

What I DID mind was how abrupt and lackluster its ending was.

Ancano was a pushover, you never find out just what exactly he was doing with the Eye, you never hear back from the Synod, and Tolfdir's just like "Hey, you did stuff, here you're Archmage now" and that's it. Very lackluster ending with a few plot holes.

However the side quests are pretty neat. Talk to the orc librarian and Arniel Gane, they have interesting missions. Also the three apprentices have stuff you can help with. And the trainers there all have quests for you to do once you reach Master level in their spell schools. There's a lot more to do than meets the eye.