Wow you didn't like Planet Zoldath? I loved that game. It reminded me a lot of similar games I've played in the 80s. Walking around a lot, puzzling, no focus on speed or combat, just trying to explore an alien ecosphere. I absolutely loved that game, especially the variety in the different (randomly generated) maps and strategies you need to use to solve them. Especially the inclusion of aliens that give hints and trade stuff is really cool I feel.
Sure the walking is slow and the two slot inventory is annoying, but I feel just like with Barbuta, that was kind of the point of it. The walking speed isn't that slow and the map is very small. And there are strategies you can use to prevent a lot of the backtracking. The game does have the flaw of it being randomly generated, it can give you terrible (or impossible) maps. But I went and got the cherry for this game, I loved it.