I'm gonna be the asshole that brings up ELO rankings.
Are ELO rankings "correct"? Shit no. They are a different angle to the same problem.
The results were often pretty similar, especially at the top, but always a little bit different. Same thing here. Everyone's subjective lists are fine, but not "correct"; just subjective opinions. ELO is also fine, but not "correct". So they are an enlightening perspective, but don't take them any more seriously than any other list in this thread. Cheers.
http://www.fightmatrix.com/all-time-mma-rankings/all-time-middleweight/
1 Anderson Silva 34-10-0 18026
2 Chris Weidman 14-5-0 7519
3 Luke Rockhold 16-4-0 3841
4 Michael Bisping 30-9-0 3776
5 Gegard Mousasi 46-7-2 3702
6 Dan Henderson 32-15-0 3593
7 Rich Franklin 29-7-0 3505
8 Ronaldo Souza 26-8-0 3248
9 Murilo Bustamante 15-8-1 3084
10 Yoel Romero 13-4-0 2942
11 Chael Sonnen 30-17-1 2874
12 Nate Marquardt 35-19-2 2842
13 Robert Whittaker 20-4-0 2305
14 Israel Adesanya 18-0-0 2187
15 Yuki Kondo 61-35-9 2114
16 Matt Lindland 22-9-0 1644
17 Ricardo Almeida 13-5-0 1637
18 Paulo Filho 24-6-3 1576
19 Yushin Okami 36-14-0 1574
20 Kazuo Misaki 25-11-2 1436
21 Vitor Belfort 26-14-0 1413
22 Lyoto Machida 26-9-0 1379
23 Georges St. Pierre 26-2-0 1298
24 Kiuma Kunioku 35-26-9 1171
25 Evan Tanner 32-8-0 1111
26 Dave Menne 45-17-2 1018
27 Robbie Lawler 28-14-0 968
28 Paulo Henrique Costa 13-0-0 815
29 Jorge Santiago 25-12-0 797
30 Demian Maia 28-9-0 764
31 Jake Shields 33-11-1 691
32 Mamed Khalidov 34-6-2 661
33 Manabu Yamada 23-15-6 660
34 Kelvin Gastelum 15-4-0 657
35 Keiichiro Yamamiya 45-35-10 625