About this mega crossover... this thing really reminds
me of my own crossover. The fact that it's starting
out as a huge mess of characters being thrown together
without any notions of a plot reminds me of the
conception of my own fic. However, I did have a general
idea of what I was going to do: namely, a huge invasion
by a extra-dimenional race. I had some character roles
in mind already, and that's how I decided who I would use
for the crossovers.

In case you dont' have an idea for a plot yet, try to come
up with one before deciding who to use, rather than create
a plot after choosing who to use. Then again, it might work...

Anyway, a note to the author or whoever's writing it:
As Keener said, keep things in perspective, and don't
stick in too many people for the heck of it. It can be
fun, but you'll really need some logic behind it. It doesn't
matter if that logic doesn't come out in the beginning,
as long as it will eventually.

Something about this crossover business and keeping
powers down: as noted by someone, throwing Tenchi
or a bunch of Saiyans would mean that nothing else
can possibly stand in their way. In my own fic, I used
the El Hazard bunch for a particular reason. I couldn't
do it logically without Ifurita, so I came up with a way
to keep her down. <heh>

It'll happen much later than the parts which I already
finished, but so what?

Anyway, what I would like to stress is that, if you have
too many characters, the pace is likely to go slow unless
you really skimp on character dialogues, and that really
won't make sense and will put the characters OC.

Try to keep things controlled and divided, if possible.
I know I'm really wrestling with my fic because of all
the characters. Just to give you an idea of how my fic
is going, I've already written 3 parts, totalling almost
300KB, and it's still only the intro.

Well, may fortune smile on you more than it did on me!