GT-2/Red Box/Headphone amp based multi use box?

[pappasmurfsharem]

I was thinking about combining a sansamp or similar amp sim. and a H&K Redbox and a headphone amp into one pedal each having separate I/O jacks so they could be run separately or together using short patch cables. Mainly this would be used for a portable practice solution and also have the ability to plug directly into a PA or AMP

My question is. I know sometimes the sansamp gt-2 can sound odd when run in the front of an amp (vs using the effects return) presumably because its like two preamps running in to eachother.

1. Is there a way to separate the artificial amp circuit out of the sansamp to use it like a typical stompbox distortion then also be able to flip a switch to re-enable the amp simulation.

2. Is there a H&K Red Box schematic that has the 4x12 2x12 combo switch in it.

3. What is a good Headphone pre-amp circuit that would be useful in this type of all-in-one