Best exercises to increase punching power?
 

Please no one disgrace themselves by suggesting I pump up my arms lol

Shake weight beeeoootcheeees.

Work on technique, most of your power is generated there. On the bag slow your strikes down until you can perform them as close to perfect as you can get, build the muscle memory so when you do speed up the form is automatic and the power will come. This means months to years of bag work repetition, repetition, repetition.

P.S. ever have the dream where you give some dude the best shots you have in combinations and dude is straight voorhees stalking you... I hate that shit.

Definitely master your technique first. Once that is perfected and you have a foundation of strength developed, you can do things like lighter dumbbell over head presses, dumbbell bench presses, or resistance band punches, really anything that recruits the same muscles as a punch. Make sure when you do these exercises for 'power', you execute the movement as quickly as possible while maintaining control.

Punching-Power
 

Agreed technique is very important but you asked for exercise based advice/suggestion

3 words,

Clap-Press-Ups