Routing question

[L.Angulo@t-online.de (Luis Angulo)]

Hello there,
Excuse my ignorance but i am still mistified by effects routing. I notice
that my GP 100 sounds cleaner when i put into the effects loop of my tube
amp, specially the delays and reverbs,but the distortions seem to have a 
bit
more punch if it goes directly into the input of the amp. Today i tried to
put both my GP 100 along with my Korg A2 into the effects loop and it
sounded weird. Am i only supposed to run one effects processor into one
effects loop? I wonder how fripp and belew do this. Here is my set up maybe
you have some better suggestions:

GR 09 out to GP 100 back to GR 09īs return.( this way i can mix the synth
with the GP 100īs sounds separate from each other.) GR 09 stereo outputs  
to
KORG A2 (stereo inputs) out to amps.( this way i can proccess the synth
sounds with the korg) EDP in the effects loop of one amp, Boomerang in the
effects loop of the other.

Problem 1: since the GR 09 only has 1 return, i can only take one output of
the GP 100 into the GR 09 and the signal of the GP is not in stereo.
2: The EDP has CD quality sound but is mono and the boomerang sounds very
lo-fi and a bit noisy in comparison.Not that great when i am trying to do
stereo orchestral string soundscapes (Yes i know you are thinking of a
solution buy a second EDP!)
3: i would like to route some analog stomp boxes and wahs through this 
small
rack. I tried to put them into the effects loop of the GP bit they sound a
bit noisy.
I ve been checking out some of this rackmount mixers like the DMC ground
link and the expensive sound sculpture. I just donīt know if this would 
help
or bring more noise into the signal.Does anybody use this?
Is it better to run digital effects processors and preamps through a
separate power amp or does it make any difference using combo amps?
I appreciate your experienced suggestions guys!
Thanks
Luis