Genuine old school feel, without all the bullshit that old-school suffered from, meaning great.
Of course, since it got rid of old-school bullshit it has to be subject to modern bullshit, as seen in the fact that it's a roguelite, which isn't necesarily a bad thing, but it could use a good ballancing act or two in the RNG.
First turn-based stealth game I ever had genuine enjoyment for. I'd rather it have designed levels, but if you want to keep it rng, hope you tweak the system to perfection eventually.
In short, with a bit of balancing, this game could become a bite-sized modern classic, and those quick rounds make it perfect for a party game. Hope to see it improve and grow in popularity.