Optimum polish with a white pad is about as gentle as it gets if your using Optimum products. You could try Poli-Seal, but that's more of an all-in-one cleaner/filler/sealer rather than a defect-removing polish.
I would say if you're going for defect-removal, you're pretty safe with OP and the White pad. If it doesn't work you can step up to an orange pad. I've gone against some of the conventional advice on this board and used it with a yellow pad. It worked to remove the defects, but its more work because then you have to go over it again with a white or orange pad to remove all of the micro-marring induced by the yellow pad. I probably wouldn't try it again but it might work for you if you have really bad swirling and spider-webbing.
If you really want something less abrasive, then go with either a final polish, like I recommended previously or some kind of All-in-one product that will fill small defects, clean the paint, and then seal it for protection. Optimum Poli-Seal, Klass AIO/SG combo, or XMT 360 would work. You could also try any number of the pre-wax cleaners out there.
