Ah, nothing better than waking up and seeing questions answered. Thank you Rebelbeta!
The graphics style will be the main graphics, but at some point, I'll invest some money for a proper graphic designer and add alternative tile mode for those who can't stand letters. Before I do that I need to see the crazy destruction related stuff I want in v0.3 because I'm worried it won't translate well into tiles and I don't want to restrict myself yet. ASCII will be the primary graphics style. I think it works better in terms of clarity, immersion and it will allow adding more content in v0.4 very quickly, which will help replayability (hopefully it will result in more contributions from the players too).