It took me a bit to realise, honestly, but I might be going a bit too big and such? 

So far I've got the basic outline of two of seven floors of what's currently called The Spiral. Now that Does sound worse than it is, since that's... Five rooms so far? Six if we count the tiny labyrinth as seperate from the room it leads to.  

Should I try and tone it down?

That seems perfectly reasonable to me but I think it’s a case of personal preference tbh. They’re called megadungeons for a reason

Six rooms sounds perfectly reasonable to me. I think if I were to establish a limit it would be to limit submissions to no more than three A4 spreads.