Smoker is not changing anytime soon, as he doesn't care about promotions and is too insubordinate for the WG's liking. Neither Akainu or the Gorousei would support him for Admiral, but he can achieve something lower.
Actually, Smoker does care about rank after Alabasta, since he needs it to be able to be better able to pursure Luffy. COuple this with him being one of the first marines to transfer to the New World after the war, and I see him as a strong possibility, especially as we always knew he was strong enough to merit a higher rank
I agree that he is strong enough for higher rank than comodore but I do not think that he will become admiral even if he's strong enough for it. He is too much like Garp, who was strong enough to be offered rank of admiral way back when Roger was still alive, but Garp refused say it'd "cramp his style" meaning he wouldn't be able to focus so much on chasing Roger. Admirals do have other duties …. like being on call to strike if someone just punches an Tenryuubito.
Some have added the link where Smoker said they needed rank, showing he does care for promotions. What the people who are supporting "Smoker for Admiral" are forgeting is that while Smoker does want smoe promotion, its only so he can go to the New World and continue to chase Luffy. Smoker said that about rank after reading on the Strawhats progress.
That is why he wanted the rank in the first place = to have the ability to leave one side of Grand Line for the other as he chased after Luffy. However, being an Admiral would limit his ability to chase after just one pirate
Why make Coby admiral when he wasn't even captain at the war where some vice-admirals showed how good they are? Onigumo was able to cuff Marco while Coby wasn't able to fight there. Sure he could(and I believe he did so) have improved in the two years but there are vice admirals that have far more experience.