I still hear of this from fans that Saban bought the footage with the Decade and Shinkenger team up so is this true? So far there has been offical news about this, but I hope this doesnt happen because it could lead to the same mistake Saban made in 1994.
Decade also had a Black RX's world which lead to a teamup with Black as well. This could be very interesting to see how they can use that world. Dragon Knight will also be interesting since that series did have many differences to Ryuki. For the other rider worlds they could use the original stories from those series and not Decade's to give potential to new riders series even though they are before Decade.