Not a complete answer, but a few ideas thrown in. 

In baking, if you add dense, hygroscopic, sticky liquids, they can make your cake heavy and dense. Try doing it with your pancakes. Instead of using a milk-based liquid, try a fruit puree, preferably one with sufficient pectin (e.g. apple mousse). If you are using baking soda and buttermilk, you will probably have to switch to baking powder because you will be missing acidity. I don't know how much you need, it might turn out that you don't need leavening at all for your intended thickness. 

Another thing to change would be the flour. Try using bread flour or whole flours to get less rise and fluffiness and some chewiness. 

Increasing the sugar will probably help with both density and crispiness on the outside. You probably can't go up to chewy cookie amounts though. 

I haven't tested any of those, it might turn out that they don't work.