Any deal that results in Sprint still existing with any of it's current C or D level executives is a non-starter. Sprint is dying and has been for years. They were great once, but they lost the plot and it's probably impossible to recover with their current team who doesn't seem to understand the problem. Right now they're focusing on trying to regrow their customer base without taking into consideration why they lost their customer base... which is that their network is absolutely terrible by modern standards.
T-Mobile on the otherhand has never been great, but they definitely know how to grow the business and how to keep many of their customers enthusiastically happy with them. T-Mo is the fastest growing carrier and the first to try out many new ideas that are definitely changing the industry. Verizon and AT&T are following T-Mo's lead on many things. Any Sprint merger with T-Mo would probably be Spring just selling off their IP, Network and customers to T-Mo and then we have a STRONG challenger to AT&T and Verizon.
If Sprint does a deal with anyone other than T-Mo, such as Charter, then the deal will be wholly irrelevant. Sprint doesn't need a cash influx, they need a ground up restructuring that replaces their entire leadership team. The best way to do that is to stick the last sword in this dying bull and let the assets be used in a positive and productive direction.