Ronto Roasters in HS. We always get one regular wrap and one breakfast wrap, two overnight oats (or whatever they call it) and two coffees, then we share the wraps. It's enough to keep us going well beyond lunchtime. This is probably our favourite QS breakfast.
Les Halle at Epcot. So many wonderful options you practically can't go wrong. It's just hard to find seating.
Most QS at AK are....acceptable. Nothing to write home about but not inedible.
MK we usually end up with a breakfast sandwich at Starbucks as there's not a lot of options. We prefer protein and savoury for breakfast over sweet so we tend to avoid doughnuts and cinnamon buns and the like.
At most of the resorts, if we're not doing TS, we just go to the main quick service and get the standard breakfast offerings. Not fabulous but not bad. And at least there's usually enough seating.