LOL.
The steam achievements will change your life ? I think the developers can add easily the achievements. The popup is very small in a right bottom corner, and if the developers create dark pictures, that don't disturb the player.
You don't imagine the number of peoples who buy the game if he has achievements on it.
I think that will be a great idea, and I think I will buy it if the game has achievements.
Just look at this link :
http://steamcommunity.com/groups/100pAG
More 600 players like unlock achievements in this group. I think the developers can sell more copies of the game is they add achievements.
I should buy the game now if I know if achievements will be on the game.
Please, add achievements with dark pictures in order to don't disturb the player.