John
You are right about the changes to the 15th, it is very polarising. Personally I liked the look of the old green complex with it's unusual front of green island bunker, however the green was always softer than all the others on the course, which I understand was behind the motives for it's re-build. However the green surface itself is now horrible, there are a lot of slopes on it which are not in keeping with the greens on the rest of the course, in particular there is a shelf in the back right hand corner about 100 sq foot, which is just horrible, but they keep putting the pin on it.
You are also spot on, the new 2nd and 3rd have gone from being gathering greens to ones with very severe run-offs, they are also (and this may be temporary while the new turf beds in full) very difficult to run the ball onto. If you think about the 12th green as it was for the Scottish (and since it's rebuild by Steele) then they are much like that. However the 12th has now been lowered, and while maintaining some of the run-offs, they are much less severe and the complex itself looks much more natural and in keeping with the course to me.
The 4th green has been altered less, and in my opinion, very well done. They have introduced some more banking with marram grass on the RHS, and removed the midgreen pot bunker. there is also now a run off behind the LHS pot bunker which protects the front left of the green.
A few photos I took a while back:
First is the new 2nd green from the fairway before it was put into play, and then again from the 3rd tee the first time I played it.
The next shows the work done to the 4th green from the fairway
As I said I'll get some more when I'm next there that show the extend of the changes better, but it could be a few weeks, as I'm off on holiday next week.