Yeah, your S&T skin looks nice.
I've decided my main complaints are:
1. Lack of consistency. Specifically - back buttons all over the place.
2. Unnecessarily available buttons. E.g. Why do you need a minimize button on every skin. If the front end is doing it's job, you don't need to minimize it. Having to go to a main skin and/or open a menu to get at it is perfectly acceptable.
3. Unnecessary UI. Who really cares what format or bitrate your audio is in. I care what's playing (and even then - really only when the track changes) and that's about it. I don't need to know what the volume is set to - if it's wrong I adjust it but knowing it's at xx% or worse, having an enormous slider that's difficult to use by finger anyway is just a waste of space. But then I'm biased since I use my HU for volume control still

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I'm working on RR improvements to suit my tastes. Next on my list is a way to have a notification skin slide in on skin configurable events. E.g. A 'new track started playing' skin that slides in from the top at the start of the track and provides the track name and then slides out again after 5 seconds.
On my skin I'm probably going to go too far the other way. E.g. I won't have any volume feedback or a way of adjusting the volume on any of the main skins. I might get around to making that available off a menu but it won't be a priority for me since I have a much more user friendly knob on my HU

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