I can't speak for anyone but myself, but I was not "caught by surprise"...I knew it was coming, just didn't know what it would be with the way this season went on this current scoresheet and the feedback that was constantly rolling in and complaints being made. It was released to coaches several weeks ago, then the update last week, so it wasn't as back to back as it seems to the general public. As a coach, I appreciated having a few days to digest it and start to learn it myself and speak to kids about it and prepare them before it became fully public so I could educate myself before parents started with the "OMG DOES THAT MEAN MY CHILD WILL BE LEVELED DOWN" (disclaimer, that's a big possibility).
Personally, I think it's a big step in the right direction. I think the update may have "over-corrected" a little bit, but I can see them continuing to adjust it to get it closer to the original in the next few seasons.
As for the drivers part of your question - those are "difficulty" drivers. They've always been there but never been quite so spelled out, which left a lot of room for interpretation. The clarity of those is a huge reason I'm mostly here for this scoresheet, because in theory I will know way more solidly where my teams difficulty score should lie all season long, instead of fluctuating within range (with the same routine, we would go from 3.6 to 4.0 depending on the comp, and it's infuriating). Execution drivers still exist and will be applied accordingly on that side of the scoresheet.