Suddenly I think of something...
I wondered why Yamato care for VF-11B, which is not essentially a hot valk, and they need to do the engineering for transformation. The production cost is high too (comparing to a Spartan, which they are reluctant to issue). Of course they can issue some color variations. But it wouldn't be a big hit with "Yamato original" colors I guess, after all it's not a VF-1, 19 or 21/22.
M7!
According to Mac Mech Manual, there are the Millia 11B, pink 11B, and three other canon variations of 11C. And there's a 11D too.
Now that justifies the engr and molding cost!
And so while I was considering about getting a VF-11B next week, I am thinking twice. I may get the Millia 11B instead later. (I am a blind follower of M&M) Depends on the price... But it seems that we'll have more variations to choose from.