3 story packs and the price for the game + dlc on psn is $80, so the pass is only $20 unless there's some kind of discount added for getting it bundled.
I wouldn't expect too much out of these dlcs. It gives me the feeling that they'll be an hour each of story content with another hour or two of very small secondary tasks.
It's actually just €10 extra on the EU store to get the digitial deluxe with the DLC pass. I think some of the price on the US store is for the physical pin that is included in the US digital deluxe. There is of course a discount involved for getting it bundled, so the stand-alone price for the pass is still unknown.