Various problems with Nike Apple Watch

I've owned the Apple Nike Watch since last November so several months in, I've ran into a few quirks, problems, etc - hoping someone has a fix for some of them or get me to the right place to document all of the bugs I've come across.

Problem 1:

I have a pair of Urbanears Hellas bluetooth headphones, iphone 7 & apple watch series 2 Nike edition.

If I listen to my headphones from my iphone and then let's say the next day I go somewhere without my iphone but take my apple watch - I'm unable to listen to music from my watch onto my headphones. The only way for me to connect my headphones to my watch is to disconnect them from my iphone first and then connect it to my watch.

I have tried connecting the headphones to the watch through the settings on the watch as well as forgetting the device and attempting to repair them with my watch (and setting my headphones to pair mode). I spent 15 minutes today attempting to connect them without using my iphone and it was impossible.

Problem 2:

If it's nice out I will run around my block only using my watch and headphones, leaving my iphone behind at home. After passing my house and getting out of range of my iphone, the music will stutter and stop for 5-10 seconds and then start playing again. Once I come back around the block it appears that my watch will connect with my iphone again and then when I start running away from my house I will get the stutter. I never get the music stutter anywhere on my run except after I pass my house.

Problem 3:

When I run on a treadmill my watch does not check my heart rate more frequently and most of the time not at all. I do not have workout power saving mode on. Is there something else I'm supposed to turn on

that tells the watch that I'm working out and to check my heart rate more often?

Problem 4:

I have to place my watch under water at least once a week to get the crown to spin freely or be able to press the crown button in, otherwise it's hard to press. Is this common?

Problem 5:

Today I started a run on the nike app on my watch. After running more than a mile I realized my watch didn't tell me when I hit my 1 mile mark so I checked it and the app was no longer on the screen. I reopened the app which asked me if I wanted to run, so I had to start yet another run. I checked my nike activity and the run in which I had started first doesn't show up of course. This is not the first time this has happened.