For some reason I thought this said modern only. I'll do a classic one too.
1 • Ian & Barbara (top overall)
2 • Ben & Polly
3 • Leela
4 • Zoe
5 • Jamie
6 • Susan
7 • Turlough
8 • Vicki
9 • Harry
10 • Liz
11 • Sarah Jane
12 • Victoria
13 • Tegan
14 • Jo
15 • Sara Kingdom
16 • Mel
17 • Steven
18 • Peri
19 • Nyssa
20 • Dodo
21 • Adric
22 • Ace
23 • Romana (& K-9)