The Problem is in the Brushing

Okay, after applying various methods in my attempts to shade the comic, I have finally come down to one of two conclusions about the shading process differences for Photoshop and Paint Shop Pro. I've tried various techniques for shading (Vinnie D's was good, but still not producing the desired result. ^_~) in Paint Shop Pro only to have the shading, most of the time, appear stilted and unusual. Now, the pictures in the Cast page were done using Photoshop, but frankly I hate Photshop's user interface and other aspects of the program, so while it's fantastic for making nice looking pictures, it doesn't work for comic pages.

Now, I believe I can get the desired result in Paint Shop Pro and there are two possibilities as to why it looks so bloody bad in PSP in comparison to Photshop:
1. The standard airbrush I use is not soft enough like the one used in Photoshop.
2. The two programs simply have different methods for how their paintbrushes work, particularly when it comes to stuff like burning/dodging.

Now, #2 is worthless to me since I can't change the programs. However, #1 is something that might be useful, so I'm putting out a call to any of the wonderful readers I have to point me in the direction of some installable Paint Shop Pro brushes (particularly soft ones). Anyone? Eh? Eh?