7. Ace
Ace was what you can call a companion. Strong and brash with a particular penchant for explosives, she beat up a Dalek with a baseball bat, had her own homemade brand of explosives and could generally be a real headache to the Seventh Doctor at times. In short, she was absolutely brilliant. Her run was unfortunately cut short when Doctor Who was cancelled back in 1989 and when the TV Movie hit screens she was nowhere to be seen. For starters it would just be great to see her back. Fans have a lot of respect for her character and remember her fondly but to see her chemistry with Capaldi's Doctor would be amazing, too. Much like Seven, Twelve would probably disapprove of her explosive tendencies but how would he react to having such a strong and self-confident character around? Clara has stood up against the Doctor quite a few times during the latest series but Ace is something different. She's a tearaway, even violent, and definitely not the good girl that Clara Oswald most definitely is. It would make for some interesting episodes, that's for sure.