Regarding Life, I can't remember much about it just a few months after seeing it. When it took it's cues from ALIEN it was okay - one of the better rip offs - but it wasn't very memorable and had no real themes worth pondering.
Covenant does a nice job of exploring David in greater detail, and of shifting the alien creatures away from insect heirachy B movie cliche it had drifted into, steering it into something much more menacing and Gigeresque in tone. Whether it's Hammerpedes or Neomorphs, these are creatures I could see coming from Giger's nightmares, perhaps via Hieronymus Bosch, but anyway far more connected to the tone of the horrors in ALIEN.
That along with the return of the Croissant ship, means that Scott's films are referencing Giger far more than any other director has, and David's workshop suggests to me that Scott is also playing with the idea that the Character of David in his new creative role is a meta interpretation of Giger himself to a certain degree - a man that designs beautiful horrors.
Very far from R.I.P. Giger, IMHO.