I would certainly NOT like to see Air India's BHX ops transferred to MAN. As a consequence of ethnic distribution, the West Midlands has a very strong case for offering non-stop schedules to India. If flights switched to MAN it would likely be just a matter of time until BHX lured them back. That is not helpful to either city.
What I would welcome is a standalone Air India operation from MAN in addition to the BHX scheduled service. The North-West is home to a population of ethnic Indians, albeit on a smaller scale than in the Midlands (ethnic Pakistanis and Bangladeshis are more concentrated in the North West). And it is important to facilitate trade with India, a key BRIC nation with a long history of links to the UK. Finally, but not least, India is very much on the tourist trail. The risk of terrorist incidents remains a threat to the long term health of Indian tourism. But barring this, the Delhi - Agra - Jaipur triangle is one of the classic tourist itineraries on the planet, before even considering popular beach destinations such as Goa and Kerala. Plus, India is a magnet for certain niche tourism markets such as enthusiasts of steam railways.
MAN should strive to build its own scheduled link to India. But it should not be a replacement for the larger West Midlands market.