Honestly, I think Marvel's solution with regards to the new set-up of Amazing Spider-Man makes a lot of sense. As Stephen Wacker has mentioned, you're talking about a dollar less per month than you're currently paying for six less story pages. And if it addresses the production issues that were eventually beginning to pile up under the old "three times a month" system, then this is likely the best solution.
And if you HAD to choose just one of the "Brain Trust" to write the series, Dan Slott is probably the most logical choice. Don't get me wrong, I am looking forward to Slott's run on the book - I think he'll do a great job.
But boy, it's going to be too bad to not get to read regular Spider-Man stories from guys like Mark Waid, Fred Van Lente and Joe Kelly anymore.
Hopefully Marvel does, indeed (as they have alluded to doing), give us a lot of side mini-series by those creators to make up for the "loss" of them from the main title.