Bengali Colony is mainly a residential area. Predominantly it caters to the old Bengali traders of Indore. If you are staying there, you might get cheap houses but commuting won't be a problem as you can easily reach Palasia and other commercial areas.
Do you know Khajrana Square? It is like an easy landmark near Eastern Ring Road. From there you just take the Nahar Shahi Wala Road by the Khajrana lake. Bengali Colony is pretty close by.