Did anybody else totally wish an Orange Ranger had popped out for Carrigator? Sorry, I just always wished there'd been an Orange Ranger. That was my colour as a kid.
Gai Ikary unless you count Samurai Ha-oh with the Kyouro Origami which is technically a 12 origami combination and while yes the Kyouro origami isn't required, it's still a possible fragment. You could also count hyper ground Gosei great which is a 15 header combination plus datras, so in my book it doesn't have the most POSSIBLE mecha, but probably the most REQUIRED mecha.
your right Dekaranger has 10 rangers, Red, Blue, Yellow, Pink, Green, White,Black,Gold Silver and Orange. I think they have the most Rangers on one team