As a Nexus 6P owner, I was somewhat disappointed that the leap from that phone to the Pixel is minimal IMO. The three things that pull it ahead are the tweaked camera, better optimization between hardware and OS, and Google Assistant. But, leaving out water resistance, a move back to a single speaker (vs. the dual speakers of the Nexus 6 and 6P), a scratch-prone partial glass back, and the higher price point were turnoffs for me. Having said all this, and as Mr. Mobile pointed out on AC, the intent is the phone to bridge the best of both what purists want (the Nexus line) with what the mainstream consumers want (Samsung, LG, Lenovo/Moto, etc.), and so far, this is working.
I feel the app experience that people complain about wouldn't be so if devs caught up to hardware advances faster. But keep in mind that unlike iOS where you're serving up one phone series and tablet, there's literally hundreds of iterations of Android devices in the market. Devs have to design the apps to work with the majority of them, from say an entry-level device all the way up to flagships. For instance, I'm as of this writing running my 6P on the Dev Preview to Android Nougat 7.1.1 (nearly identical OS as the Pixel). Some apps are crashing just because they've not gotten up to speed to the new OS.
Sort of on a sidenote, why the heck did they not change the charging ports for the iPhone 7s to the USB-C standard? People may rag on them, but you have a number of Android flagships that can natively connect to the 2016 MacBook Pro and 12" MacBook, but you can't do the same with the iPhone 7s.