These Match ups can involve fighters in separate organizations that you most would want to see fight each other. You can even pick a match up between fighters if they are only a weight class apart or so.
Mine for each weight class would be:
Chad Mendes vs Frankie Edgar - I feel this fight would consist of a lot of energy being expended between them both.
Men's Light Heavyweight:
Alexander Gustafsson vs Daniel Cormier - This I feel would be the #1 contender for after the Jon Jones or Glover Teixeira battle taking place soon. Since Cormier is still undefeated, I feel a win should grant him a title shot at the Light Heavyweight title.
Junior Dos Santos vs Antonio Silva - I picked this match up because simply put, I feel someone would get finished here.
Looking forward to other people's ideal match ups out there.