Top 7 based on WGP wins :
1 Souwer (2x K-1, 4x S-Cup)
2 Buakaw (2x K-1, 1x S-Cup)
3 Petrosyan (2/1,5x K-1, 1x Glory, first tournament was 4-man)
4 Masato (2/1,5x K-1, extremely helped by FEG/Tanikawa)
5 Kraus (1x K-1, 1x WLF, some low tier tournament)
6 Roosmalen (1x F&F)
7 Groenhart (1xK-1)
I still consider Buakaw and Souwer as elite fighters although both are way past their primes.
My top 10, partially based on achievements :
1 Buakaw (defeated Petrosyan but got a draw and he's still the biggest treat to his
throne)
2 Petrosyan (reigning kingpin in kickboxing, lacks the balls to compete in any other
ruleset, such as FMT, Shootboxing, etc.)
3 Souwer (most WGP wins, Kyshenko being his kryptonite)
5 Roosmalen (unless he lands a lucky shot he won't defeat Petrosyan, dutch style)
6 Ristie (could deliver an upset against Petrosyan because of his awkward style and
being a southpaw himself)
7 Groenhart (highly overrated, but has potential and could suprise us)
8 Kyshenko (has/had potential but lost a lot because of mike's bum squad)
9 Kyria (has potential and a chin, hasn't proved anything yet)
10 Grigorian (brings pressure, lacks big wins)