I'm kind of meh on the clock tweaks and the mound visit change. If teams get an extra visit for the 9th if they have burned through their 4 in the first 8 innings, then I don't see this as having a negative impact. There are just so few times that 5 visits are used before the 8th that I've thought the mound visit thing was an unobtrusive rule that only came into play when visits were being abused. As for the 20 second to 18 change, I think it's not going to be too visible but I don't think it was needed. When you couple it with starting the clock when the pitcher receives the ball and not when he's on the mound I think it'll have a bigger impact. There are times between pitches when you want to check the defense, disrupt runner and batter timing, and catch a breath.
The baseline thing is so overdue.