Pad shims

Beveled wool felt shaped to fit the front of the Ghost panel. Two pieces per side, use the bigger one alone for a 1/4" lift, both together for a 1/2" lift. You can also shim one side more than the other if your horse has a bigger shoulder (shim the smaller shoulder).
To install, turn your saddle upside down on a level surface. Remove one panel only and open the velcro tab. Push one or both shims to the very front of the panel, close the velcro and reattach to the bottom of the saddle, using the stitch line of the base for positioning while comparing to the panel still in place. Repeat for the other panel.

Wedged shim inserted between base and closed panels. Perfect for those who want the classy look of the closed panels (especially with a matching color/material) but need a little lift in front to balance the rider for horses who might be downhill where the saddle wants to side or who have less curvature than the Ghost base. These work great with velcro opening panels too, and sometimes are a bigger solution than the felt shims that can go inside the panel. This is also the best balancing solution for the western saddle. Sold in pairs.

Ghost makes an extremely nice pad, especially for the very reasonable price. Many people buy these for other saddles including BMSS, Freeform, and even treed saddles. Bottom material options include sympanova (a soft rubber, easy to clean, breathable), black, brown or white wool blend, and an amazing medicinal sheepskin. I recommend 1cm inserts with sheepskin unless rider is over 185, and for other bottom materials unless over 165 or horse's spine is well protected.
Add embroidery with your horse or barn name for extra fun!
I keep mostly black with various bottom materials in stock. Others will have to be ordered from Italy.

For those who want a cheaper option or more ability to customize, I've made some less polished seat reducers from wool felt. And here's a hint - if you have similar material laying around, you can make your own or even do other customizations to the fit of your saddle.
These are made from 1/4" thick each and can be used with 1-3 (maybe 4 if you adjust the position of your seat back on the base). Typical use is 2-3 for ~1/2" to 3/4" smaller seat