[Scribus] Arranging Complex EPS files into a larger document?

[Greg Novak]

I deperately want to use Scribus.

I am making a scientific poster, which in practice means collecting a
bunch of plot and images I've made over the past few months and
putting them together with a little text and perhaps a few line
drawings into a nice looking 3ft x 4ft document that I
will print on a large format printer.  These plots and images tend to
be EPS files but they can be rather diverse.

Scribus chokes on the more complex EPS files I feed it.  It takes a
long time to convert it and there are problems with the images.  Even the
simpler ones seem to make the text look funny in the conversion.

I would in fact be just as happy if Scribus _didn't_ convert the EPS
files to its native format.  I'm eventually going to export the whole
thing to Postscript (or at least I have in the past) anyway, so if I
can just place boxes where I want the plots and then have them show up
in the Postscript output, that'd be great.

As it stands, the only program I can find that seems to do what I want
is... Xfig.

So I guess I'm asking asking:
0) Am I crazy for trying to do what I'm trying to do?  Ie, is there a
   much better approach that I'm not seeing?
1) General tips for dealing with importing EPS files and arranging
   them into larger documents?  Should I convert them to something
   else first?  I'd like to avoid rasterizing them.
2) Any links to battle-hardened tools for converting between vector
   file formats?

Thanks for any guidance,
Greg