The Juusangouki has similiar rotating things on its hand, when it detaches its second pair of arms from its chestplate.
So does Yui's Divesuit. They probaly do magic, of which more is needed for beastmode.
Sadamoto noted that it was supposed to be a next-gen Model of plugsuit (Just as her green Suit represented the plugsuit generation before what we saw the Nerv Trio wearing), Kaworu's Mark IV has similar "White thingies" on it.
It makes sense that Shinji's newly comissioned EVA 13 suit would be the newer NERV/SEELE model. It doesn't look any newer than the Mark 6 or the pink plugsuit because TI either made all designers go splat, or leave NERV/SEELE.
As for Rei's, it's the boob-protectorless variant of Mari's second suit. The green things suggest similar design patterns, but it couldn't be *too* different from her 2.0 suit because parallelism/"shadow" motif. Somehow, the female plugsuit always has a version with boob protectors, and one without. Asuka always has them, Rei never does, Mari appears to be variable, since she has a boob-protector-less version of the WILLE suit.
Which makes little sense since she has much more boob to protect than Asuka does. Then again, maybe Asuka wears them so her boobs will look bigger in her plugsuit XD
Alas poor Kaworu, I knew him well...