Avoid Oily Runoff: If you are using an unmixed natural peanut butter (one that naturally separates with the oil on top), be sure to fully stir the PB before measuring out the cup - this will help avoid oily runoff while the cookies bake. I use a flat knife and stir like the dickens (great workout!). If you still get some oil in the baked cookies, just rest them on a paper towel to absorb excess. It will dissipate quickly.
Unsweetened PB: I used an unsweetened natural peanut butter in this recipe and determined the amount of maple syrup accordingly. If you are working with a sweetened PB, you may wish to adjust the syrup content (although this can sometime influence the result - the syrup assists with binding) so my best suggestion would be to wait until you need more nut butter and opt for unsweetened for the purposes of this particular recipe.
Allergies & Preferences: As mentioned in the post, you can experiment with any nut or seed butter here so don't be deterred by the use of peanuts in the demo recipe. Both sunflower seed and pumpkin seed are low allergens.
Additions & Substitutions: As mentioned in the post, feel free to sub other fruit/nuts/seeds in place of the chocolate in this recipe. Adding liquids (lemon, mint, vanilla, etc.) may influence the outcome though, so you might wish to start with increments (1 tsp for example) and see how the recipe responds.