This is pretty interesting. Keep going.

Ranma is accepting this rather passively. He's an active sort of fellow. 
Might he try to put a failsafe into the plan that none of the women know
about? If you know the original Star Trek episode where Kirk gets
cloned, you know how he produced an inaccurate duplicate by tampering
with his thoughts during the process. Maybe Ranma can also find some way
to tamper. At the very least, like Spider-Man back in the 70's, he might
want some way to know who the original is.

Idea:  Is it possible that each of the the Ranmas will wind up fleeing
one fiancee to go to another for comfort or advice? Or that the five
Ranmas would even switch partners from their original assignments?

I would suggest slowing down in your portrayals of the five girls. Now
that you've got the basic situation on paper, when you finish and go
back to revise, maybe add a scene or a few scenes in which you establish
your particular take on their personalities BEFORE the cloning happens.
Akane doesn't come off at all sympathetic in this piece. Is that your
intention? Whatever suits you, but in most source materials, Ranma seems
to like her at least some of the time.

DRM

-- 
My signature file, attending all mails:

Neither titles nor eloquence do we require, he said, nor an insidious
tongue
nor familiarity with saffron myths on painted scrolls, but patience to
disengage difficulties until matters disclose their essence without
opposition, because the most subtle understanding outweighs mountains.
          -- from Evan S. Connell, _The Alchymist's Journal_