You conveyed the desolate nature of the world well! First impression, the piano in your first track is too loud. It could use some automation and velocity reduction, with some added reverb to add more to the soundscape. The elements with the drone-like strings are nice, however. The harmony design was hard to follow in the 2nd track. Might have been because of the muddiness of the strings and the strict quantization, which makes it sound delayed compared to the piano. The 3rd track is my favorite, with the way you used the synth ostinato in the back to convey a sense of inevitability. The detuned, sliding strings were a nice touch too, to add an apocalyptic vibe. Almost gives an Interstellar OST vibe! Try to do more dynamic and automation work with your VSTS. There are some good ideas that are held back a bit by the dynamic being one-note and loud. Nice job!