In a small bowl, whip the peanut butter and butter until creamy. I did this by hand but you can do it in a mixer if desired. Add the sugars and whip until creamy. Add the vanilla extract, salt, oats, flour (add the flour slowly in case you need slightly less than recipe indicates) and stir until just combined.
The dough should be easy to work with and form into balls at this point, but if the dough is too dry or crumbly and not coming together, add a touch more peanut butter until desired consistency is achieved. Conversely, it dough is too wet or sticky, add slightly more oats or flour. Also, chilling the dough in the freezer or refrigerator for 20 minutes prior to shaping it into balls can be helpful if the dough is a little wet or sticky.
After appropriate dough consistency is reached, fold in the chocolate chips and then roll the dough into ball shapes. After the balls are rolled, if you choose to apply a chocolate drizzle, I recommend chilling the balls in the freezer for about 20 minutes prior to drizzling with melted chocolate so it hardens on contact.