shooting in JPEG is fine but ONLY after you have mastered your aperture and WB controls, and also reading histogram on how to identify overexposed, under, low key, high key, etc photos.

stick to Parameter 1 for walkaround shots, use 2 for portraits so that it doesn't make the subject's skin look like shiny plastic and instead apply a soft touch effect

I was fortunate to work with one professional wedding photographer for a day. He said dial the sharpness to the max, which is +4 because DSLR soften the picture automatically. After that, I use Unsharp Mask in CS Photoshop to make if further clearer, though not too extreme. The effecy is amazingly clear!

Professionals won't tell you much about PP, they'll tell you to use FILM