Ok... Well, right of the bat, Current Strange seems to have a little push, but he won't compete with the top 3.
Rulk is to one-dimensional to also compete with them.
Really, it's between Jordan, Martian Manhunter and Beta Ray Bill.
I think that Bill's hammer negate most of Manhunter advantage he could have. Jordan is, IMO, the most versatile, but not by a long shot above Bill.
IMO, here's how it goes:
1- Hal Jordan wins it, but Beta Ray Bill has a great shot at the first place too. I give a really small edge to Jordan because IMO, he's a tad more versatile. That's it.
2- Beta Ray Bill
3- Martian Manhunter
4- Rulk
5- Strange