There's a lot of tops that love to suck cock. It's just part of great sex and their cravings. As a highly preferred bottom, I love to make my Sir explode inside me, and get the pleasure and satisfaction that he craves and deserves. But I don't think most tops want to suck a load out of the bottom's cock. They're still being a dom, Just sucking it because they love cock!! And then have the bottom, or themselves, stroke the bottoms cock to orgasm. Which I've only had done to me 1 time. All the rest have ended without me cumming. Which is just fine. I rarely ever think about me having an orgasm until well after we're done. It's all about making him happy. This is all based on my own experiences and interactions with tops. I'm sure there's tops out there that want that load in their mouth just as much as me lol.
As for being vocal. I love it. Everyone's cock has a unique pleasure sensory, so I always tell my top to let me know when I hit the good spots while sucking, and riding them. After all, we all want the experience to be as hot and pleasurable as possible. Damn, now I want a cock!!