I gave another read to the pre-Gauntlet Thanos stories in the old Captain Marvel (Mar-Vell) issues and Adam Warlock stories by Starlin after many years of gathering dust in my bookshelf. The backstories of Drax the Destroyer and Gamora and how Mar-Vell got his Cosmic Awareness power impressed me most. On the other hand, comparing them with the movies makes them seem like ineffectual goofball jobbers by comparison to their source material. 70s - 90s Marvel comics had a lot going for them before the Speculator Boom happened.
It is kinda funny; the original Thanos stories in Captain Marvel and Warlock were the closest you could get to auteurism in the 1970s mainstream comic industry (frequently, the only thing Starlin wouldn't do was the letters) and they were basically cult hits among people who were impressed by the weirdness and philosophy of those stories. They ended up being a significant source material for arguably the least auteur-ish (that description is not necessarily a bad thing) and highest-grossing films of all time.
I think Warlock could get a little preachy about religion and individual freedom at times, and Starlin's jab at the then Marvel editors with the 1000 Clowns chapter was a guilty pleasure, but it was clearly a very personal project for Starlin and the Death of Captain Marvel was really one of the best and most moving Marvel stories from the eighties. I was really upset the MCU reduced Mar-Vell to an old lady who got killed off in such an un-memorable way.