#4 Have the new number one contender Ambush Ronda Rousey
WWE doesn't have a lot of time between now and The upcoming TLC pay per view which is why they need to quickly introduce Ronda Rousey's next opponent for The Women's title. With that being said, the best way to go about this would probably be to have Rousey cut a promo in the ring and then be interrupted by the new number one contender.
Not only will the move give the new number one contender a lot of credibility for having the guts to interrupt Rousey, but it also gets the ball rolling for a match at TLC. WWE could even have the new number one contender ambush Rousey after a match or promo and build the feud from there.
If nothing else, that would be WWE's best shot of jump-starting a feud with so little time and getting fans interested in it as well. Maybe WWE has Ember Moon be the one to win the number one contendership, turn heel on Ronda Rousey and then knock her out with her signature eclipse finisher!