Development 2 - JetPrivilege is now allowing you to redeem JPMiles across a ton of airlines (not just their old partners) through here - https://flights.jetprivilege.com/

And you can literally redeem any seat not just award seats (typically O, X, I class) across a whole bunch of airlines at the most absurd rates possible. They say it's any seat and I'm inclined to believe it's (almost) any seat. I think these rates have been set by SBI - that's the only way it could be exponentially worse that 9Ws. Also, if you purchase tickets at these rates SBI might approach you to buy their stake in 9W so do it at your own peril.

I have screenshots below but here's the summary. I looked at BOM - JFK return in mid Sept and here are the rates (drum roll please):
Economy - between 303,400 and 539,400 miles OR between 1000 miles + 1.96 lakhs and 1000 miles + 3.5 lakhs! BTW the 303,400 miles / 1k miles + 1.96 lakh option is for a United flight that costs 89k to buy outright.

Business is even better - 950,200 to 1.696,400 miles OR 1000 miles + 6.16 lakhs cash to 1000 miles + 11 lakhs cash. The lowest option is on UA again 950,200 or 1k miles + 6.16 lakh for a flight that costs 2.6 lakhs to buy outright.

Only a million miles to fly to the US and back in business! So if you were looking for the worst way to burn your JPMiles - you've just found it. Redemption rates @ ~27paise / mile if it's an all mile transaction. I can't calculate the 1k miles + cash deals!

I can't imagine there is better pricing on other routes. More importantly I couldn't be bothered to check - but if you find something let everyone know.

You can complete the entire transaction on the website. If you're short of miles you can buy miles @ 65 paise/mile while doing this transaction. Which is pretty good. So you don't have to spend 1.96 L to purchase a 89k ticket! Instead if you have only 1k miles it will cost you 1,96,560 to buy the balance miles.