As a professional scuba diver, what do you regret?
Not much. Less free time, but that is about it.
What would you have done different in view of your current experience?
Maybe waited a little longer before starting.
What traps would you have avoided?
Forgetting that sometimes you have to dive for yourself, at your highest level, keeping your skills honed.
What shortcuts would you have taken or not taken?
None. Shortcuts have no value other than to get you someplace faster. The experience of getting there makes for a more proficeint diver & instructor.
Which sacrifices were worth it, which weren't?
It can be tons of physical labor to prep for a class, but watching you students grow,... priceless. Being in the "people business" you can meet some interesting & also some unpleasant people, you must learn to deal with them all,... think outside of the box at times.
Which skills outside scuba most helped you with scuba?
I was a martial arts instructor for 7 yrs before I started diving. I already pretty much knew how to relate things into simpler terms to make learning easier.
And what advice would you give for someone who is starting their career?
Take your time, get as much experience as you can in all environments- Deep water, shallow water, still water, currents, warm water, cold water, clear water, murky water, daytime, night time, good buddies, poor buddies. Then find the best instructor you can who teaches & expects you to teach beyond the bare minimums. Once you start teaching, take some time off here there to dive for yourself, or else you will likely very quickly burn out. Also keep learning yourself. Keep your skills sharpened. Never forget that you were once a beginner yourself. Relate to your students' issues.