im pretty sure gokaiger alredy did that with the mini megazord line :lol

I'm not talking about the mini Mugenbine megazords.
I'm talking about a DX Mugen Megazord, with the ranger's suits having ports to allow for parts as well (Like, every character could have an "Armored" form that, could be replicated by the toys by taking the DX zord pieces and attach them to the ranger toys (While in show they'd be miniature parts because scale is a bitch like that :p)).

masked sentai ryukirangers?

Dinosaurs and trains? Count me in! Two of the coolest motifs out there.

I know right?! I'm imagining this T-Rex Locomotive rising up from the tracks and doing damage!

I was actually thinking of things like helicopters, motorcycles, etc, but whatever.

What kind of train do you think they'd use?

I would love if they used something like an old Steam Locomotive. Like a Peppercorn. But, being Japan, I think we're looking at some sort of futuristic bullet train. Like that RiD combiner.
What I'd really like is each Mech become a train car for one long locomotive. Instead of having each one become it's own train. They tried a hybrid of that with Super Train (I don't know the Japanese name), and that didn't look good to me. It tried to be both a long train, and individual trains.

Are you talking about a shinkansen?
Anyway, while the idea that each one becoming a car would work to keep a coherent train sounds fine, that pretty much means that only Red's car/engine would have any sort of individuality...

In Train Mode. But then the awesome of them changing into Dinosaurs come in. But, I think, if we get anything it's going to be another Shinkansen (Thank you by the way. I have a hard time remembering Japanese names for these things). Which is fine. Not as awesome, but fine.

Oh. I was thinking you were talking about something like Go-On, where they were trains with animal faces on them, not straight up transforming trains (Which would be awesome).