Dan Slott still has it in him and he's still a good job with Superior as it is, but I still hold JMS as my favourite Spider-Man writer and I'd go as far as to say that Bendis would do a fantastic job as well. After all, Spider-Men was my all-time favourite Spider-Man story in the past several years.
I know it hurts that Peter is gone, but assuming he'll be back soon (really, how long is Marvel going to keep their most popular character dead?), I'd like to see where Dan Slot is going with this. I've always enjoyed his writing, and Superior hasn't disappointed me so far, despite Peter's demise. And seriously, Peter WILL be back, even if it's after Dan Slott's run, so I'm no to worried on that front. Stupid Marvel and their pointless deaths.
As for the suggestion of Yost writing Spidey? He'd probably do a good job, but I don't want a premature end to Slot's run. I want to see his master plan.
I liked New Ways to Die, The Gauntlet, Grim Hunt and Ends of the Earth.
To be honest though, I'm really kind of bored with his run now. Give someone else a chance like Christopher Yost, Brian Michael Bendis or hell as Greg Weisman if he'd be interested in writing Spidey comics. (It wont happen but I'd love JMS and/or Peter David coming back).
I wouldn't mind seeing Yost take over writing Superior should it get relaunched or something following #31. That being said I love Slott writing Spidey. I think he's one of the best Spider-Man writers around and beyond Stan Lee's stuff in the beginning I can't really think of an extended run of Amazing that I like all that much besides Slott's.