The tomb I gave her is the biggest in the fortress and covered in masterwork statues and the like. And I tossed her some steel armour.
Good job. Back to topic: Does it help to get down when dodging arrows and bolts?
I asked this to Toady on another thread. His response:
3. Grounded units cannot be hit by projectiles until their "ground effectiveness" kicks in, unless they don't have one in which case they can always hit. For shots or thrown projectiles, this is the range of the shot (or maybe that -1). The idea was to have them pass over intervening grounded guys to hit their intended target. However, people mostly shoot at the closest enemy, so it's mostly for you in adventure mode. I don't think there are any other modifiers for being prone, though there reasonably should be.
So you can be shot over, but it doesn't seem to make much difference if they're aiming at you and are good at shooting. It also does double damage if you're on the floor, and your decreased speed will increase the number of shots they get in. I wouldn't advise it much.