LOL. You make it sound like the S didn't have black bars at all when watching videos, when in fact it did, they just weren't as wide as on the Tab 2.
And while the resolution did go down a very small amount (359ppi vs 320ppi), this was because of the change in aspect ratios (16:10 vs 4:3). Both are still 2k screens.
The Tab S2 came with the fingerprint scanner, while the Tab S lacks this feature all together. One of the reasons why I bought the Tab S2 over the S.
As for your comment on a flash for the camera on a tablet.
Talk about reaching. If you are using a tablet to take pics, you have more serious issues to deal with.