Airmos
Tomorrow's underwear!
In my observation I personally tend to find that if anything the themes tend to be shaped more so by outside trends. (Especially when it comes to Sentai) For example Gokaiger is pretty obviously pirate themed due to the success of One Piece, similar to how Hurricanger was a ninja series due to the insane popularity of Naruto.
If this is true, then I sincerely hope that My Little Pony isn't popular in Japan.
