One thing to watch out for with tracking synths in stereo is that a lot of the patches and FX are set up to be hard panned full L-R. When you get a bunch of these tracks on top of eachother you end up with a "big mono" sound.
If the instrument sounds the way you'd like it to out of the box, and summing it to mono doesn't totally trash that sound, you could print it that way and then add your own spatial effects. My new favorite trick has been using a wireless transmitter (it's helpful to have a video gear collection sometimes
) and pump my tracks into my living room with a mic and track that as a chamber reverb. Sounds WAY better than any artifical reverb in my price range.
Or maybe you can play around with the panning on the output of your synth. My ancient Yamaha TG55 can do that, so you can have some things fully wide and some other things not necessarily mono but not spread as wide in the soundstage.