Think of this whole thing as a stepping stone in your life and quite possibly... someday, you might be opening an even bigger and better shop and you'll have had all this experience, plus from your new job to put to use later.
Definitely. Be a sponge as far as management practices you are seeing around you, even if things don't seem to be as green as you now see it. You will leave with the knowledge you feel you're missing now.
Wish you the best...not luck, because you have proven to be a man driven by desire and action. Just wish you the best!
jc