Layers on Map and arowslits

[Lord Of Darkness]

I have been playing the game for quite a while now and I love it but one of the things I have been thinking about lately since the addition of the Deep drill mining is getting the colonists to dig underneath creating a new level. When I create a base its usually in a mountain but If I want to expand I need to use the same level/floor. but as people have been saying don't make it that easy, like have the colonists have to build supports into the rocks to stop floors from falling through and increase the chance of infestation. I hate sometimes my wee guys have to walk ages from there room to the kitchen or the exit of the colony for a few hours then head back to there room. this could also be good for basements ect.. even put in hazards like flooded if its near wetland ect.., Would not mind if you could build archer slits for deference .