I like when random dungeons are allowed to get a little bit crazy. I used to play a lot of ZAngband (roguelike) and sometimes a floor would be super small, which often meant that it was packed with monsters and items. Other floors would have huge open spaces (like almost the entire level). It really helped to break up the monotony of predictably sized hallways and rooms. It made things more fun to explore and also introduced strategic decisions, for example when entering an open-cave style level you could easily aggro too many monsters and get surrounded, so finding a safe spot to use as a home base was more important.