Are we keeping the old arcade style?
like see how far you can go then reset?
There will be an ending, but it's not something you'll be able to achieve easily.
Edit: Think in terms of spelunky, dungeons of dredmore, and faster than light.
i liked the ascii characters, it was really interesting and original
i also liked the ascii characters, but it's your game, do whatever you want with it.
You can still switch to the ascii style, the monsters, characters, and dungeon are all re-skinnable.
By default the game will include at least two skin sets, the ascii and a more conventional sprite set.