I feel the same way. Mine's a 15 S. Had it since Oct 2015.
How many miles/km are you at now?
As far as crankwalk goes, just don't think or worry about it. It's happened to stock cars and modified cars.
I'm at 75k miles now. DKM since 62k. I used Ceratec as a preventitive measure and let off the clutch right after cold starting my car. Keep up with regular oil changes and let things warm up before pushing.
I strictly do 5k mile interval oil changes.
I don't see any benefits from custom tuning in your case. Not mine either; I'm basic bolt ons and EQT stage 2.
EQT has great tunes. 5150's THOTS tune looks interesting too.
Take care of your car and it'll take care of you. Congrats on paying it off and enjoy your car!!