That laser focus which nets you an A and makes the impossible a reality is a huge asset. Not everyone possesses that personality trait/skill - hone it, improve upon it, ride the hell out of it. It comes in handy at work - but, here is the rub - in a professional work environment it will hurt you to revert back to C mode. It labels you as unreliable and inconsistent, which is exactly the way to get overlooked for the next promotion.
Anyway, welcome to the forum:) I am impressed that you are working on controlling your impulsiveness, it is always worthwhile to improve and change oneself. As long as you remember that you cannot control and change other people, you will be way ahead in the game of life.
The mess and clutter - wish I had tackled that tendency at your age. I was the opposite, I rebelled against an uber strict parent who was beyond uber clean. I swore the second I moved out, I wouldn't do a thing for a month, not my most intelligent or even rational decision ever.
It is a good thing Mr. R. is neither impulsive nor messy, but I still am to a degree. Funny about folding the laundry, he does not fold and put away whenever he does the laundry. Whereas I consider that simply a part of doing the laundry and can't understand for the life of me, why you wouldn't immediately put it all away, since the object of doing laundry in the first place is to remove the mess:) Go figure.
Perhaps in your case you are just now coming into your own - unfolding into the person you really are.
Do check the investment and the ask a mustachian thread. You might also be interested in the "Throwing down the gauntlet" thread and even the decluttering thread. You see, you are in good company here:)