+1 for this, would love the ability to look ahead when shuffling a playlist/album/all songs and remove certain specific tracks. Poweramp must already know somewhere what's coming next when shuffling (presumably it knows the full list of what songs are coming and in what order), so giving the user control over this queue would be great. As others have said, this is the only "standard" music player feature that Poweramp lacks, and the one that makes me want to change to other apps the most.
I'm used to the one from Google play music (rip), but other apps (Spotify, musicolet) have this ability, so anything like that would make this the perfect app.
I know it's possible to work around by selecting all tracks I want to shuffle (e.g. all songs), adding them to the queue, in queue re-sorting the list with a random order, and then removing songs, but this is a lot of steps to achieve something that is usually one button.
