We just got back and I can say that MM+ worked great. I can see how it would make money for the company because I was able to do more and spend more time with my family as opposed to running around and getting FPs (and we are savvy Guests who go each year)
I only saw strategically placed CMs helping people and I guess I past some of the kiosks, but frankly they were not obvious unless you where looking for them (with the exception of the one at the restrooms between Adventureland and Frontierland.
As far as "Beloved Features", loosing Sid's ranks pretty low, the building is still there and in the future can be something else once the need goes away. I mean let's face it, an autographed Tony Danza 8x10 wasn't adding to the experience of DHS. I'd be calling for them to kick Sid to the curb if they hadn't because while it may have been neat on opening day, for the last 10 yrs its been schlock.
All around property the FP+ worked great for us, from preplanning to making changes on the go. The one time either I or the system deleted our upcoming FP for Soarin, I was able to talk to a CM and she fixed it for us in under a minute.
As far a missing things, I do miss the fountains in Adventureland, but I understand why they don't have them anymore, they are expensive to maintain, people let their kids play in them, and they can be dangerous. As for Sid's, try and understand that it is gone for a reason and that for now it is serving a purpose, that purpose will probably change in the future, but don't knock a system that is, in the end, going to make WDW easier for everyone.