I didn't go to the Correr Museum or the Doge's Palace last year, but my trip-prep notes include this comment, which I think was based on info posted on this forum: "Buying at Correr no longer guarantees fast access; ticket-holder line very long." Quite a few ticketing shortcuts either are no longer available or don't work as well as they used to. I think there used to be a staffed bag-check facility for San Marco, the use of which got you into the church without waiting in the ticket line. They've switched to lockers (reportedly), so that quick-access option is now gone.
Quite a lot of the museums covered by the pass in Venice are fairly minor ones; often I like those, but in the case of Venice, there just wasn't much that appealed to me, so I have no experience using that pass. I did buy the very inexpensive Chorus Pass, which covers entry to at least a dozen less-famous churches. I was in Venice for about 9 days but spent a lot of time taking advantage of Glass Week. That gave me less time than I had expected for seeking out the churches, but I still at least broke even on the pass, which is good for a year.
By grouping your most transportation-intensive sightseeing (especially to the various islands) into one of your weeks, you might be able to avoid buying two, one-week vaporetto passes. They cost 65 euros each in Venice. Individual rides are 9.50 euros.
I'd recommend booking the Guggenheim (really excellent if you like modern art) ahead of time, once you're in Venice, rather than just showing up. It's very popular, and you could otherwise end up in a significant ticket line. The Accademia was a just-walk-in museum for me.