Hi & welcome to PT.

What jumps out at me is the statement " I took him through a few of the basic behavior/obedience courses. He learned the basics, and still follows them fairly well to this day (sometimes with a little stubborness)."


I believe he needs more training in the basics. If you are not sure the dog
really "gets it", then formal training would really help you both. Training
never ends really, & talking him on walks & reinforcing commands might be
a good idea too.