You're not specific where your shorts are "bunching up." Are they riding up your legs? Smaller shorts, longer shorts, or different leg grippers might help. Are they twisting around your legs? More panels, maybe.

If it's the chamois itself, my thoughts are that it should more or less match your saddle. I prefer a more T-shaped saddle with a cut-out, and similarly I don't do well with shorts that have a whole lot of padding in front. PI chamois definitely have a wide front part and they're made of material that tends to fold rather than compress. And you want to also make sure that the chamois is wide enough in back to protect your sit bones.

More panels basically means the shorts are going to "stay put" better, because the more panels, the fewer different directions each panel has to stretch as your legs move. But if the shorts fit you well, they shouldn't "bunch up" regardless of the number of panels. Just more panels will move around less. Be prepared to pay $12-15 per panel.