This is my go-to chicken marinade (from my original manual that came with my first Weber)....and, yes, it has vinegar in it, but at the right proportions, and balsamic vinegar is quite different in flavor than straight, white vinegar:
1/2 cup soy sauce
1/4 cup balsamic vinegar
1/4 cup oil (corn, veggie, olive....whatever floats your boat!)
1Tbsp dried oregano
1tsp dried basil
1tsp garlic powder
1tsp onion powder
1/2 tsp black pepper
I either reserve some of this for basting, or simmer it up after the chicken marinates in it (15 minutes kills off anything nasty.....) I find that basting every 10 minutes or so really puts a great color (and flavor) on the bird.
Good luck, keep at it, you'll hit on a recipe and process you like!
Rich