It would be nice if the ability to swipe on the now playing could skip the track. For example, a swipe on the now playing widget to the left would skip to the next track. The directions can, of course, be customised by the person.
You can probably get the general functionality you're looking for using a two/three/four finger swipe setting!
Currently using swipe left/right for volume. I tried assigning four finger left/right swipe to PREV/NEXT but it's common to trigger more than once depending on how far you swipe.
Just to be able to toggle prev/next buttons on the Now Playing widget would be nice here
You can adjust this if I remember correctly by adding a percentage of range - but I might mistake this and think about the slider 
Sliding on a widget could be difficult if it's not fixed to the left/right side of the Touch Bar. Alternatively you could assign a tap to go to the next, and a long tap to go back. Or like on your headphones: one tap is play/pause, double tap is next song, triple tap ist last song. You find the code somewhere in the forum.
An other possibility would be my Preset where you can hit the cover to play/pause, the song information to the next song, holding the cover to go back, and holding the song to open iTunes. Or you can change whatever you want, the idea here is that you can interact with the song information and the artwork.
Yes, i had the same wish, and i guess i have a solution created for this.
You control spotify with just one button. 