I doubt there will be a final Ash pairing. Apart from his brief crush on Gizelle in The School of Hard Knocks, he has not been attracted to anyone in all the years Pokemon has been on the air. He is too absorbed in trying to become a Pokemon Master to take notice in any girls or boys. He is also extremely oblivious when it comes to love. Whenever romance is in his face, he simply does not get it.
I cannot stand Pokeshipping. Ash and Misty have clashing personalities. They are both too dominate and aggressive to be able to sustain a healthy relationship, since they would have a constant power struggle between them. From what I have seen of Sinnoh, I also dislike Pearlshipping. Ash and Dawn act too much like platonic siblings for a romance to ever develop between them. Dawn is also too high maintenance for Ash.
I have never had a problem with Advanceshipping. Mind you, I do not support it, but I can tolerate it. However, it will never happen, since Ash is not interested in anyone romantically (May included) and May is clearly attracted to Drew (who reciprocates her feelings).
As far as pairing Misty goes, I like her with Tracey best. Their personalities balance out well with one another. He is a calm, easy going, and mature young man while she is a short-tempered, brash, and stubborn girl. I have seen her paired with Brock before. That could work, but because I am not a fan of the pervert x hot headed girl cliché in anime, I do not support it.
I like May with Drew best. Some people have stated that a relationship between them could not work because Drew constantly teases May. However, keep in mind that Drew eventually did cease teasing May. In the last episode he was seen in during the Battle Frontier saga, he was actually quite nice to her.
Appealshipping will probably never happen, but I can definitely see why people support it. Penguinshipping is lame in my eyes (then again, I just plain do not like Kenny). I have not seen any episodes featuring Conway yet, but HeatTagshipping looks interesting due to Conway's creepiness around Dawn. I hope that I will one day get to watch the Tag Battle arc. I really want to see their interaction.
Holly x Brock seems neat, too (another reason as to why I want to watch the Tag Battle arc).