Blizzard looks like they're pulling out all the stops for Act V and the end-game, which is great news. However, I'm worried that they might leave the rest of the game "as-is", which I fear might be a huge mistake. A few examples:
Tiny Rooms
Back during the beta, I was certain that all of the side-dungeons in Act I were placeholders. The Cellars, the Grave, the Cave Under the Well all looked (understandably) unfinished. Well, fast-forward to now, and they still look like that.
What's the point? Why even waste the loading time to explore a single room with nothing of value? Even when the Cellar randomizes with the Quill Rat 'event', it's unsatisfying. These areas should be over-hauled or removed -- no half measures! This certainly includes the silly rooms in the rest of the game, too.
Other, Larger Dungeons
There are lots of randomized dungeons that are larger, but they ALL follow the same pattern. All of these have one large floor, and a second smaller floor with an Elite pack guarding a treasure chest.
In five minutes, any of us could brainstorm more interesting ideas for side-dungeons. The possibilities are endless, and so are the lore opportunities! Den of the Fallen? An awesome hideaway where Rakanishu II has been plotting an uprising? ..Oh, no. Just some skeletons, dead ends, and an unrelated random Elite at the end. The Well?! I remember that from Diablo 1! I bet I have to find some huge, toxic beast that's been leeching poison into the area.. Oh, no? Oh well.
There are games where it's difficult to inject creative quests/ideas without messing with the greater narrative/gameplay, but Diablo 3 is a canvas that is PERFECT for little "modules" of content. Hell, they SHOULD be pumping out little "plug-and-play" events for free/for 99 cents that constantly expand the world of Sanctuary, give us nuggets of lore, and open new areas to explore.
I refuse to believe that the developers shipped with these awful, pointless little dungeons and considered that their vision for the game. So I wonder, will they be revisiting this content in RoS?