How far out is safe

I have a 20' long with 10' beam fiberglass V-hull chapparell boat with a
johnson V-6 150hp outboard. Fuel capcity is 50 gal tank. Full electronics
and so forth, with optimum weather conditions seas 1-2 ft or that lucky
glass day. How far out in the ocean could i or should i go to see a little
better fishing, ie... size or game fish, without getting myself or others in
trouble, or before is unsafe or unrealalistic. I would love to see blue
water but i don't think i have the fuel capacity for that, I am aware the
1/3 rule as per fuel, 1/3 out---1/3 back and 1/3 for just in case. Not that
it would make any difference, i would be going out of either south jersey,
delaware bay or delaware or O.C. Maryland.

Any help and or suggestions would be greatly welcome, I would like to bring
my kids, 14 and 18, but only if it's possible and safe to do so, if not,
chances are i would be doing it alone Most likely as i do most of time.

THanks in advance