Here's a few tips for you, Sunny.
Don't restrict yourself to the default reverb settings. By that I mean, don't restrict your playing to one reverb for an entire registration, style, or bunch of styles. The Genos is so dynamic that you can assign reverbs to each individual part in a style.
The general idea is to add a little more reverb to parts that are playing background and less reverb to the solo instrument. This gives the effect that the solo instrument is placed closer to the audience on a stage and the background instruments are sitting more backstage - just the way you'd hear it during a live performance.
Try panning your non-soloed instruments left and right. Picture how a live orchestra would be seated on stage. Strings on one side, brass and woodwinds on the other, percussion in the middle, bass in the middle. Yamaha does some basic reverb and pan settings but you can play with these settings as much as you want because they are just a guideline
Large orchestral type songs tend to have a bit more reverb, depending on the size of the hall in which they play. On the other hand, if you're playing a "pub" style song like you would hear in a small bar or pub, there would be almost no reverb.
The whole idea is to picture the location where your style and song is used. Apply the reverb to match that setting. Half the fun is discovering how to get the sound right. Either way, enjoy!