Our family is similar- husband Moroccan, I am American, our family language is English and we are raising our 3 and 4 yr old in the US. My husband has exclusively spoken Arabic to the girls since birth (OPOLOne Person, One Language, OPOL). Depsite this, books and DVDs in Arabic, English dominates b/c they know they can speak in English and be understood. We don't have any Arabic preschools, probably similar to your situation with Hindi. The one I will add to much of the good advice is don't underestimate the power of 3 things:
- Playmates in the target language. As your child grows, get a group of kids together who are being raised with Hindi. Having the influence of other Hindi-speaking kids is a huge positive influence.
- Extended visits from grandma/grandpa
- Trips to India (the only time when our girls have been forced to speak in Arabic is trips to Morocco and although they struggle at first, once they realize no one else understands them, it really helps). Unfortunately, making trips every few months is not a reality but even the yearly/ever other year trip helps.