Hi, personally I think white looks best on Ertiga. You might have noticed that maximum Ertiga's around are in white. Apart from looks, white color has other advantages like better visibility in dark, heat reflection, etc. But if white is not at all an option, then have you considered Ecru Beige color? I have noticed it looks good on actual car. Grey and Blue are also common so you might want to take a look at Ecru Beige.
Also the AT version is supposed to launch by this year end. Not sure about the date, you may ask your near by dealer to give you a call when bookings are open for it. However I am not sure if you are aware that AT mileage is bad in City and good on Highways, so think if you really want AT otherwise a better option is Ertiga CNG. Again these are my opinions, final decision is yours