The mechanics are very solid and the functional upgrades really give a cool Metroidvania style progression.
The game world is nicely large for the sake of exploration, but I found myself really wanting some kind of item to clue me in on at least the next direction that I should look for something important. Maybe it's just me being spoiled with that type of mechanic as prevalent as it is in a lot of modern games, but the feeling especially started to sink in at the point where I needed to find the tablets. Something like a sonar pulse that goes out and makes an icon for a point of interest in a direction relative to your current position, just so that I don't feel as aimlessly wandering at times.