I was pretty disappointed in Season 4 as it unfolded, but I am OK with the last couple of episodes and how the series concluded overall. The cut to black and then follow on Mask Collector was enjoyable.
They just really wasted a couple of episodes with the time jump. I thought for awhile that it was going to be a dream sequence. Making Sally a pathetic alcoholic and making Barry uber-religious did not make much sense to me.
Small complaint, but my wife and I love to point out "glitches" to each other, which is what we call incongruities in shows between scenes. And for me, Barry's facial hair was infuriating. One scene, he has a five day growth, next scene (same day), it is a five o'clock shadow. Seemed like the last two episodes were really sloppy.