Interesting. I thoroughly enjoyed Outer Wilds (no "The" btw) and Return of the Obra Dinn and would say they are two of my favorite games ever, but I just could not for the life of me get into The Witness. I was just plain bored after a few hours.

Well, different strokes and all that I guess. Anyway, I strongly support your recommendations.

Same here. As well as Outer Wilds, I recommend Obduction, it's from the makers of Myst and is the most similar game I've seen to Outer Wilds. There are also Talos Principle and Antichamber, a couple games clearly inspired by Portal. Talos Principle feels like Portal 3 to me, while Antichamber is a non-Euclidean version of Portal.