Lets talk about the companions from the start of the reboot to the end of Eleven's run.
Those would be, in order of appearance:
Rose Tyler
Mickey Smith
Captain Jack Harkness
Sarah Jane Smith
Martha Jones
River Song
Donna Noble
Amy Pond
Rory Williams
Clara Oswald
I rank them from least fave to most fave and give some rationales. There might be slight spoilers. Proceed with caution. <3