There was a thread on indian take-aways last year but not on restaurants so would be interested if you go back in and find that it's good.
We used to like the Dewaniam but since their schism although the food remained good the place was like a morgue. For the same reason I have never been in Elachi as it never has any customers.
The Dartmouth Tandoori has really friendly staff and good service but the food is pretty greasy.
Let us know how you get on returning to the Indian Gate as I have a curry feeling coming on.