I agree that the sprites are too small to appreciate. Also the camera is quite behind the player, so it is difficult to see what is ahead when walking along those long corridors. Having the option to play fullscreen would also help.
The sound and music made it very clear when I was detected and when the stopped looking for me, so that is a big plus.
I got caught once or twice, but most of the times I could run by the enemies unharmed when they chased me. That felt good to pull off, but maybe there could be a punishment for doing that a lot to prevent abusing it, like making the enemies shoot or run faster after the third time they miss hitting the player.
Overall it is a bit short, but a fun game.