I like this. It's very minimal, and I love the repeated note sequence the piano does at 0:28. This, combined with the strings, creates an evocative composition that isn't quite stable musically, and that's what makes it really interesting.
The addition of the electric guitar sounds was a good idea to help "open up" the piece as it progresses while still maintaining the continuum in the background. I just wish the sound design was better - not that strings, piano and electric guitar make for a bad combination in this, but I think a minimal piece like this relying more on atmosphere and emotion needs sounds that are a little more "human", more akin to how they would sound in real life. This is especially apparent in ambient/atmospheric music, where a good portion of evoking the atmosphere does rely on the timbres to create said atmosphere. As noted below, you should consider doing things like varying the velocity, especially in the acoustic instruments so it sounds less "robotic".
I'm reminded a bit of storybased RPGs, especially at the beginning, but I can see this piece working in a game of that sort. Overall, nice job.