I have been many times to Cafe Mickey for breakfast (and for dinner), and it is NOT comparable at all with the standard hotel breakfast (which I actually really like, btw!)
At Cafe Mickey, You have the choice between many different kinds of breads, rolls, croissants, etc etc etc etc etc etc. There are al kinds of cakes, muffins, pies, ...
It has eggs, bacon, sausages.
It has a HUGE choice of different cheeses and "charcuterie" (how do you call that? Sliced meats) Also, there is smoked salmon.
Fresh fruits, jams, jellies, honey, butter, ...
All kinds of drinks.
I really like it!!
A nice extra are the characters, that come around, by EVERY table!! I was "scared" at first that they would ignore us (two "adults"), but no, they came to our table too, and not only for pictures, but they played with us!!! Especially Chip and Dale. And I think I kissed the bad king from Robin Hood's feet while at cafe Mickey!
I am sure I forgot many items, but it REALLY is a nice breakfast.
I don't know about the plaza one. I know that, before, it used to be Cafe Mickey and Walt's. cafe Mickey was buffet, while Walt's was à la carte (which I didn't like that much, I'm a huge breakfast eater, and don't want to be limited to one plate!!)