Honestly it one of those " if you have to ask" questions.

How about a simple indoor soil grow? Why invest in something you dont really know about? A soil grow is a very cost effective and great yielding way to go. Easy to manage and wont get you down.

Growing in soil you have a buffer when you are learning to care for a plants needs with the soil. DWC and aero both require knowledge and a costly setup to pull off correctly.
Very worth it if you can manage it, otherwise a waste of time.

16 1-2 foot plants? I would reccomend more like 6 to about 48". In soil.

Bugs outside are fairly easy to manage. and ec and ppm are 2 completely different ways of measuring kinda the same thing. Think you will be ok with a ph meter and ppm pen to start out.