[Surfkat]

While not a reamping trick, here is how I often record synths direct. I have a pair of OSC mic pres which have both input and output gain and they have line level 1/4" inputs on the front panel. The synth feeds these 1/4" inputs in stereo then the output of the pres goes to a stereo compressor, usually a Drawmer Merc 1969. I can play around with the I/O gain on the pres and the make-up gain on the comp. Lots of room to play there for varying the sonic textures.

Also I am a big fan of synths through a tube guitar amp. This can open up a whole world of mics, placement, room ambience, spring reverbs, tube overdrive, etc.

All of these things can really help to make a synth track sit in a mix nicely alongside guitars, horns & voices.