I started playing about 3 months ago and switched to lazer about a month in, but still kept playing classic. I can't speak on some things because of that reason, mainly HP drain since I never paid much attention to it.
All slider changes except for slider head acc (in the last paragraph) feel great to me, their scoring though doesn't matter much to me. Probably another thing I just didn't pay attention to. Past that, all of it is good, especially in regards to very short sliders, because they used to be really hard to hit. Even now they're worse than spaced streams (or however it's called at my "fcing ~4* maps with some effort" level), but there's a huge improvement.
The capped spinners are great. I remember when I got my first SS and thought I would be among the first place ranks, only to learn they did spinners stupid fast and got more score for them. That's definitely a great change for newer players, I think it even motivates them to do spinners better because they have a real cap they can reach, instead of some mythical 477 rpm.
The scoring is definitely way better than it was, though to me it's now way too forgiving on some maps; on some maps I had ~800-900k highscores, and the changes didn't really do anything there, but on others I had 50-100k, then easily got ~300k after the changes for what should have been a really bad play, with like 10 misses and 85% acc. Feels a little too much. I think now that it's smoother it's way better overall, but it's not steep enough. It should punish going way above the player's league instead of giving a fifth of the max score for something they can barely pass.
The S also doesn't feel really special. I can sometimes get a score with 4 misses and a third of the combo, and still get an S for it because of fairly high acc, which feels weird. So yes, definitely something to distinguish full combo.
Also, one thing that bugs me is slider head acc - and yes, I know it's not exactly the topic, but it's important to me. PLaying stable and later classic, I got used to thinking circles are about accuracy and sliders are about tracking, and now when I play with slider head accuracy, it completely throws me off, to the point I often get ~90% scores where I did easy 97-98% on classic despite the fact maybe half of the objects are sliders. Skill issue, arguably, I know. Still, it bugs me, and I think it could be easily solved by making slider head accuracy an additional mod in the same vein as strict tracking.