The Drop Rate I felt like it was lower then 2.x I've farmed all the 3.0 cards now except Bismark so far. Most of the time it took a couple windows of almost fully winning the matches before I got the cards. I know Aymeric took me almost a full day alone to farm when Uldah was on Reverse making the NPC that dropped him very easy to win against.
I don't mind the lower % when it's only 20 new cards with about half of them only obtainable from NPCs compared to the larger quantity of 80 when it was first released