I'm definitely liking the USB C cables more than micro USB, it does take a little more force to plug in/remove but I think my micro-usb cables were like that when I first got them as well. The insertion length is a bit longer though and it feels way sturdier when plugged in. Also, the charger I was using at work (an old HTC) charger charges my 6P a lot faster than with the micro-USB and my note 4. That may just be that the USB-C cable is higher guage for charging, or maybe it's something with the charging for USB-C being more standard than the proprietary quick charge. It actually says charging rapidly with this charger, so that's a pretty nice little surprise there.
Some other thoughts on the 6P in general, this phone has amazing signal strength, totally blows away any phone I've used. At work I usually get terrible reception on ATT LTE, but I'm getting a full signal bar with the 6P. I'm going to do some speed tests at home vs my note 4 tonight but downloading apps over WiFi seemed to be a lot faster as well on the 6P.
The white color looks really nice, an the camera hump actually looks pretty nice in person, really sets it apart from other phones and it contrasts nicely with the white. The plastic band at the bottom of the phone doesn't match the white back exactly but it's pretty close, it almost looks a little silver when you look up close. Anyway it's not bad and doesn't really detract from the overall look.
So far the fingerprint sensor has been great, really fast and really accurate, I've only had one misread so far and that was when I tapped it with the tip of my finger, but I bet if I set up that finger again and used the tip of my finger during the setup it would read it.
I haven't gotten a chance to use the camera much yet, I was playing with it a little last night in very dim light and it turned out some nice photos. HDR+ seems to help a lot in low light shots, without it the photos seemed a bit noisier. Comparing it to my note 4 it seemed to produce a little more natural tones to me, especially with skin tones. Hopefully I can try some shots today with more light to see how it handles it. The biggest problem with the camera so far is the exposure imo, the Google app is using center weighted exposure which can really throw off some shots if the background has any lights or is just brighter. I want to play around with it more but to me it seems like an app that's supposed to be very automatic like the google camera app should be doing a multi point exposure to try to balance the focus point and background more.
In general the performance is great, everything is much smoother than my note 4 and the annoying hangs that happen sometimes on the Note 4 seem to be gone (such as opening the multitasking screen and the camera). Also everything seems to set to a higher DPI which makes the screen feel bigger. The camera performance in general seems quite good, if you're doing HDR shots the processing takes a little while, but it does it in the background so you can keep snapping shots while it's doing that. If you aren't using HDR it's very very fast and I didn't notice any time to process after the shot.
Battery life I can't comment on too much so far yet, I got it at 50% yesterday and it lasted me for most of the night while downloading stuff and playing around a lot, I left it off the charger at night and I think it lost 1% so doze definitely seems to be doing it's job.
Last thing for now, the speakers seemed plenty loud to me when I fired up some games last night, I haven't taken any phone calls so I can't speak for speaker phone volume but I'm quite happy with the volume so far.