I got curious about the presence of runestones in Finland. There's a page set up by a woman named Zorm speculating about the origin of a pair of standing stones at the
Raisio Church plus a mention about controversial runes found in
Vöyrin.
Now, one example of prehistoric rock art is the
Huittinen moose head made from soapstone. New tools could include chisels and files (substituted with sandstone or rough wood for stone lapping). I also looked up a bit about
rock painting. Red ochre (punamulta) from hematite seems to be the pigment, which I guess could be acquired with the mod that lets you dig bog iron. The hematite should be crushed and then mixed in egg or animal fat for binding material. Red has also been used in wooden house finishing (keittomaali) with flour and flax oil as the binder. That might be handy when deteriorating buildings become implemented!
Stonelobber's Primitive World mod has a few simple recipes for clay pottery, and I guess you could extend it with small handicrafts. However, its requirement to stand in water ends up limiting raw material collection because you can't stay in cold water for too long.