Burnett/Edwards residence wrote:

        As I have said before, this has the potential to be a good,
probably dark fic (for the girls' own safety they had better not think
Kerrigan is another fiancee)

"Ai yah!  What alien blade woman think she doing with airen?"

"What does it look like, poor human?  I am breeding."

"Look more like putting slugs inside to eat airen."

"Like I said."

which screams for someone of Biles'
caliber to actually _write_ it.  Before we get to that point, though,
there are some points I wish to (re)iterate.
        First: we have to make clear where in the Starcraft ['SC'
hereafter] timeline we are drawing things from - is this classic SC or
are the events in the Brood War expansion going to play a factor?

Classic would be better: more people know it.

Why
is this important?  For one thing, we wouldn't want to piss off a Dark
Archon, now would we?  Imagine what its Feedback ability could to to
Ranma or Ryoga... and I won't even go into their mind-control powers. 
Second: psi and chi are two entirely different things;

How do you know this?  Chi could merely be the result of humans'
attempts to manifest the energies that the Protoss have mastered in the
form of psi.

quite aside
from that, it is to be noted that the Protoss' energy shields were
designed to stand up to stuff a lot more powerful than anything the
Nerima bunch can produce (once again, whoever thought that a Mouko
Takashiba could put a Probe out of commission is, in my personal
opinion, using a cheap copout).

Depends.  Ranma would have to display a bit more power than usual, but
then, we don't know for sure just *how* powerful a Mouko Takashiba can
be.

        And leave us not forget that the Zerg combat breeds have
reaction times as fast as, if not faster than, those of Ranma and co. 
In other words, this is no cakewalk: they might be able to repulse a
_small_ Zerg force, but it's going to cost them.  They'd better hope
they never encoutner a Defiler, either.

Ranma can, on a good day, dodge bullets after they're fired.  Zergs
can't.  That seems to indicate that Ranma is faster.  It is merely
*movement* speeds that are faster (which is probably due more to muscle
and design than concious reactions; after all, if you've got the motions
memorized like you've been doing it for generations as the Zerglings
have, how fast do you need to react to run at 80+ MPH?).

One other thing: any ability possessed by the Nerima crew that entails
pulling objects from nowhere would be negated in the presence of an
Arbiter.  I don't need to elaborate on that, now do I?

True, but only for those that actually come from nowhere.  Mousse, for
instance, would not be affected: his weapons are actually there.

        With that out of the way, I believe we can proceed directly to
the conceptualizations.

It's a matter of power, really.  Ranma and company can be as powerful or
as weak relative to a new set of characters as you want them to be.
Same goes for any magic (Sailor Moon, Slayers...even technomagic like
Macross/Robotech).  Whoever's more powerful will probably dominate the
story.  Regardless of reality (as critical as I may have seemed, I
actually agree that the SC forces should, overall, be more powerful than
the Nerima crew if their repective stories were true), you'll get a
better story if all the main characters get a chance to contribute
significantly.  (Which means that Ranma can defeat a probe easily, and
would only be equalled by SC's toughest units, or "heroes" such as
Kerrigan.)