First and foremost, get the notion out of your head that you were shooting 20lbs over the trad bow with the compound. If you were shooting an 80lb compound and a 75% let-off, you would be only holding about 20lbs.
The ideas of going closer to the bag so that you learn to 'feel' the shot (shoot with eyes closed if possible) is a good one.
But you made one very important comment and asked a specific question.
1) You 'think' you are overbowed. YES YOU ARE. AS Fred Bear put it (paraphrase). "A new archer should pick a bow that they can hold comfortably at anchor for 10 seconds, and then pick one 5lbs heavier to grow into." The right bow to learn proper form on is one that is lighter weight (most suggest 35-40lbs), where you can actually see and feel your mistakes at anchor...review before the shot. Being over bowed can cause all kinds of form problems that are harder to correct than if you learned properly.
2) Your question was, "Should I learn Gap?" YES>>YES>>>YES. Even if you meld into 'instinctive' or Split-vision later on, you will have a solid foundation to always use when needed.
First and foremost though, get your bow/arrow tuned properly to eliminate bow/arrow blaming. Read and watch everything you can and then get up close and personal with your target bag. If you can afford it, and can find one in your area, get a coach!
Learn the 3Cs of archery; Control,Consistency, Confidence.