I'm a little sad that they didn't include Monk in the list of "Expert" classes. I've always considered them to be a skill-monkey-meets-Fighter class...at least as much as the Ranger is, anyway. Ah well. Minor gripe.
Woah. They included a LOT of feats in this one. But does every feat need to have an ASI attached to it now? I guess so. I don't want to believe the rumors about "power creep" but...well there's this, and there's Heroic Inspiration (that rewards you for failure). It's all little stuff, sure. Probably nothing to worry about at the moment, but little stuff tends to add up over time.
I like the changes to the Exhausted condition...much more streamlined, and probably the opposite of power-creep.
Same for "Interrupting the Rest," which states that if your Long Rest is interrupted by combat, the rest confers no benefit and must be restarted. This makes random encounters so much more dangerous and I love it. "Why yes, players, you can certainly spend the night in the Haunted Forest of Spiders and Nightmares, that sounds perfectly fine! What could possibly go wrong?"
I also like the Study action...it's expensive (it costs your whole action) but I like the way it's structured...and I especially like how it specifically puts "traps and gadgetry" under Investigation, hopefully ending the "why can't I use Perception for everything" argument at my table.