As far as the saddle goes, it looks like they still have the riva saddle--same as the one on my 2011 Vita. In my experience, it became uncomfortable after 30-40 minutes of riding. I think they described it something like "plush and comfortable" (not a direct quote, but you get the idea). Total contradiction in terms. I think you are wise to be think about replacing it now.
This is pretty much what the bike shop lady said too, and I trust her judgement.
Dawes Cambridge Mixte, Specialized Hardrock, Specialized Vita.
mixedbabygreens My blog, which really isn't all about the bike.