Really, they were all identical? Because that's incredibly wrong. Every single dungeon was different.
Sure, not all of them had something really unique and interesting going on, but they were all designed differently, they had different traps, some of them had stories involved that weren't quest-related, some of them had little puzzles here and there. Saying they were all identical is an EXTREME exaggeration.
That said, of course I'd welcome an even bigger difference between each dungeon, and with more dungeon developers, I don't think it's something that should be a concern.
While OP wrote identical, that's not what he originally meant I think.
I think he meant that they
felt identical.
To me they did. They felt pretty much the same, more or less.
After playing Oblivion for a while, every time I saw a dungeon when exploring I was like "Nah... why would I wanna go in there, it's just like all the other dungeons. Nothing special or unique. All feels the same."
Only unique ones were quest related, which you got over pretty fast to be honest.