As a fairly competitive runner (60-80 mpw, 3:02 marathon pb) I use a Garmin forerunner 230. It's simple and easy to use. Garmin has a great feature where runs are uploaded directly to your iphone/androids Garmin app via Bluetooth.
The issue is... in order to run with music I must use an iPod nano 6th generation (the square one with the screen and clip) while I run. The iPod is several years old now and has been replaced many times. It was great for a while. I loved the fm tuner for when the same songs got boring. I didn't mind paying 99 cents for songs. But after getting Apple Music and paying $15 / month... I minded very much.
I just want simplicity! A GOOD running watch that can play music (doesn't even have to be Bluetooth. I don't mind the wire). I can't run with my phone, too much weight - and running gets me away from my phone which is another bonus.
But I have almost 0 options. I haven't met too many serious runners who use Apple watches for their runs. They are just not at the same level as Garmin (lightweight, longgg battery, easy buttons to use, durability).
I debated buying the Mighty player (bemighty.com) and listen to music through that. It's a clip on music player that reminds me of the iPod shuffle. And it plays songs through the Spotify app (without having your phone on you)... but I just don't want to make the leap to Spotify. Especially with my sights on the homepod.
Why can't Apple and Garmin strike some sort of deal? This Garmin pay is a little ridiculous if you ask me. The few places along my run routes to stop and hydrate are little shops that don't even accept credit cards unless it's more than $10.. let alone any Garmin or Apple Pay.
If something were to check all my boxes it would look like this:
Garmin hardware with Apple Music integrated (along with AM/FM tuner) that allows for BT headphones.