Hello this is my first post on here. Seems like a great source of information. I was wondering if someone would be able to help me.

My friend and and I want to book a trip to London from July 6th-July 25th. We want to fly in and out of London because we have friends that did the same.

These are the points I have:
123,000 Ultimate Rewards/United
50,000 Citi Thank you's
50,000 Capital One
30,000 Delta Skymiles

We would like to travel together. Do you have any recommendations? Any help is greatly appreciated.