ImO:
Pre-timeskip
1- Dracule Mihawk
2- bartholomew Kuma
3-Donquihote Doflamingo
4-Trafalgar D Water Law
5- Boa Hancock
6- Buggy the clown
Post-timeskip
1-Dracule Mihawk
2-Bartholomew Kuma
3-Donquihote Doflamingo
4-Gecko Moria
5- Jinbie The First Son Of The Sea
6- Sir Crocodile
7- Boa Hancock
Decided not to include teach because he argueably can be considered not in their league.
Pre-timeskip
1- Dracule Mihawk
2- bartholomew Kuma
3-Donquihote Doflamingo
4-Trafalgar D Water Law
5- Boa Hancock
6- Buggy the clown
Post-timeskip
1-Dracule Mihawk
2-Bartholomew Kuma
3-Donquihote Doflamingo
4-Gecko Moria
5- Jinbie The First Son Of The Sea
6- Sir Crocodile
7- Boa Hancock
Decided not to include teach because he argueably can be considered not in their league.