I was not really thrilled by most of the standard covers for the 5.0 books. There were lots of dull muted color palettes, too many figures cloaked in darkness, and sketchy brushwork that gave a “soft focus” effect that I usually dislike. I usually prefer bright saturated colors and crisp detail.
These newer covers mostly look OK to me. I bought the new 5.5 DM screen back in November because I liked the art and because Miniature Market was selling it for almost 50% off during a holiday sale. I actually like both of the Dragon Delves covers and have not decided which one I will get. I may skip these two books though, for the same reason I skipped Sword Coast, Acquisitions Inc, and the Critical Role books. I have never really been a big fan of the Forgotten Realms setting and I am not sure how much of this material will be useful outside of that setting. Maybe I can look at the new spells and such on D&D Beyond or the wikis.