I think that if the bottom looked exactly like the top and the case was a bit shorter it would look just as good:-)

With that shape on the bottom there is enough room for some fans to take in some air without vacuuming the floor and without having to put the case on top of something while it's on the floor. So your airflow could be from bottom to top and be in line with your mobo arrangement... that is if you were cooling with air. Maybe something to consider if you decide to make a similar case in the future.