With the death of Whitebeard, Roger, Fisher Tiger, and Ace, the resigning of Garp and Sengoku, and the retierment of Rayleigh, who are the 10 strongest known Pirates on the sea!!
You cant say Big Mam or Kaidou or any whitebeard allies, I'm meaning, who are the strongest people we know can do?
Im talking power-wise, in terms of pure physical, spiritual, mental power!!
You can include Shanks, we know he is a swordsman on par with (or stronger than) Mihawk with haki comparable to Whitebeards. Any strong marine that we know the abilities of is acceptable.
We are talking PRE time-skip, ok? You can include anyone you like, as long as they're still on the sea adventuring!!
In my opinion, the top 10 would be,