I agree that one dimensional is bad, but guard-heavy doesn't have to be one dimensional. If you played four guards, two of whom were good perimeter shooters and one that was a slasher, along with a post player that could score in a pinch - that's not too easy to defend in my opinion. I'm not convinced you could consistently keep that level of talent...but if you could I think it's an interesting question whether that team would be successful.