I don't think it is necessary to make a prime Frame.
The 1' has a prime because it basically follow the design of 1, and there is no other number that can better describe this kind of design.
The X' and Hn' have totally the same design but with a better spring and the lock ring(I don't know how to call that but I think you can understand this?)
If there is a prime Frame, there can be only two possibilities.
First, if it has similar design of an existing Frame, it can just have new name. There are a lot of parts have similar design but have different name.For example, Wing and Boost, Arm and Vertical, Heavy and Gravity, Orbit and Atomic, Revolve and Eternal, etc. The reason why we need a 1' is that this is named by number, which is very different.
Second, if they change the material, it is still very unlikely to take place. Because frame is a whole part, which means they cannot do the same thing as they did on X' or Hn'. They have to change the whole Frame if they really want, but what it could be? Rubber is too soft and may not be able to fix well on Core Disc. Metal is too heavy and that would totally break the balance in metagame. POM seems have no special effect as a Frame.
So I believe that there will not be an prime (or dash) Frame. The new Frame should have a new name.
And for everytime I considered so much, the truth would finally tell me that I was wrong... XD