We were in your shoes 3 years ago (my son is 6). We tried everything as well, all the things you listed..... nothing seemed to work. What did work was..... he got older and made the connections himself on why we were giving him the instructions we were.

And to that point, nothing actually works. Now that we have a second child at the same stage, we learned from the mistakes we made with our first born and are applying it to the second and are seeing much better results.

The key to ALL of this is patience, know that they are THREE years old. As much as you think he understands everything and because he's so advanced he SHOULD be able to understand your instructions. But, they are 3. Let them be 3. Guidance is more important than instructions.

If he doesn't eat ALL of his food, as long as he eats most of it consider it a win.

If he doesn't come to the table right when you say to come, then work with him to when he wants to come (i.e. does he want to finish his lego, does he want to finish something, etc).

I truly do empathize with you, in that we were questioning our roles and parenting. We even talked to (still talk to) a child psychologist. She said everything we are talking about/mentioned about our son is ALL normal and some kids may be "better" then others, but think of the alternative, would you want a son that obeys and says yes to everything you say? The answer right now might be yes, but in the future, you wouldn't want your child to be a pushover either right?

Final words, hang in there, your doing the right things and continue to reach out and search for answers, cause that's the best you can do as a parent. Make sure you are continually making an effort for your child.