-Megaranger and Kamen Rider Fourze - Well, who wouldn't wanna see this team-up? I mean we'd have the Megarangers now all grown up actually sharing the same universe as the Space Kamen Rider Club talking about their experiences in high-school and sharing their dreams with one another and so forth. Plus it would actually fit the ideas of having yet another awesome space battle and show how two generations of two different high-schools would inexplicably have something in common all together.
-Magiranger and Kamen Rider Wizard - Of course we all know that Wizard suck, but just think what would actually happen if he jumped into another parallel universe where there are five-colored wizards that uses courage and family ties as their source of magic and then teaching Haruto how to use his "Bravery" as the final hope for himself and show the importance of him being a wizard and a hero and vice versa. Not to mention that we'd see more magical combos between the two series, when you at least think about it.