Yes, groups are still too tough.
I can almost beat a group of high grays now, but I quickly lose to a group of low greens.
I haven't done a mission yet, but that's going to be the key since when you select an "Easy" mission, the opponents are generally only one level below you (i.e., high blue) and often in groups of two or three.
So as it stands right now, soloing a mission would be impossible even on the Easy setting.
But, I'll be testing more to get more concrete data.