Onstartups has a great article and a very excellent read about what to do next AFTER your MVP (Minimum Viable Product) succeeds.  I think it should be opened up to a debate: Should you BUILD IT BETTER (MBP) or should you BUILD ANOTHER MVP?

My argument for building another MVP is: why ruin a good working product?  By definition success means its working.  STOP.  Let it work.  Build something else!

My other argument for building another MVP is: your current MVP is probably not working.  DO NOT Go from MVP that fails to Maximally Viable Product.

Finally the ideas that make an MBP good from the article, probably should be PART of your MVP!