The features >> workflow board is great, no doubt! However, there's one view I want to see that you don't offer, a plain board not independent of assignment.
I don't care who the work is assigned to, I just care where it's at in the pipeline. When you have 20 people on the team, the board can get quite messy (if you select everyone). It's nice that there's a granular level to go down to but when you don't need to see it, it would be nice to de-select everyone and see a clean board of just features, and maybe put the assignees name in the card.