One particular feature I like is the ability to edit while playing the audio at 2x speed, which I use to do a quick first pass where I remove obvious things like dead air, coughs, uhms, etc., before doing a second pass at 1x looking for finer details to fix. However, I've found that this feature has been worsened a bit since v6, so I've been stuck at v5 this whole time despite the many new releases. Every time a new version comes out I try it out immediately, but so far v5 has been the superior one for my particular workflow.
I'm not complaining though, for as long as Ardour 5 still runs on my computer I'll be a happy user, and I'm very grateful for Ardour's existence, but I wonder if anyone else uses it the way I do and if they've had the same issue with newer versions.