I have the same pad Appsolute has, and use it in the same way (under my jumping saddle for trail riding, sometimes with a thinline pad - hey Appsolute, great minds think alike, lol!). I use this pad because it just seems to “set” the saddle so much better than any other pad. No billet straps or keepers, and yet everything stays nicely in place over hill and dale…AND YOU CAN PUT IT IN THE DRYER!
I do think the coolbacks are slightly less bulky than the woolbacks (having owned both). That being said, I generally use the same saddle with a fleeceworks wool pad for jumping, so the saddle fits her well with a thicker pad. I don’t think, however, that your saddle has to be monstrously wide for the pad to work. More like a good fit on the wide side…