The neoprene pad that you are talking about is called tacky tack. It is sorda a waffle weave and does work really well.
Carrie,
Saddle fitting is a huge a problem. If your horse looks more like the walker body type and moves out like that then you are faced with the extra shoulder movement. If she took after the quarter type, then you have the problem of width.
I would check out Circle Y new line of flex tree saddles. They are to mold to the horses back. I do not think that these saddle will work if you try to use them for Roping but they do fit several body types.
If you use your saddle for Roping then make sure to get one that is specific for that. It will have a stronger tree for that sport.
If you run a search for saddle fit, you will be able to get some info on how to see if the saddle fits the horse or not. One test that I use is, if after I have ridden for several hours and my horse has worked up a sweat, when I remove the saddle is there any dry spots. If there is, that means one of two things, the saddle is fitting to tight in that spot or there is a gap/air pocket and the saddle is bridging.
Keep in mind that a poorly fitting saddle will not make the ride pleasent for the horse. Your horse may develope a bad attitude.