Will this make a good grilled chicken marinade?

Yes, but the lemon juice will make the chicken tough if the chicken is left in it for too long. It depends to some extent on the ratio of lemon juice to oil, but I never marinate chicken for more than two hours when lemon is involved. Two hours is plenty of time!. (The marinade is not penetrating the meat, so even 20 - 30 minutes is enough.). ;o)

Absolutely! I would also add a little salt.

My absolute favorite!!!

Yum. Yes