No not scary at all

try it!
It's good for highlighting.
Get a stiff brissled brush
Mix a lighter Colour paint that's suitable
Use a tissue and get most of the paint off the brush
Starting at the top, use a straight stroke down the surface
If you feel confident and there isn't much paint on the brush you can scrub around in circles if you like. (that could be good on the wall to represent the plaster the builders used) but keep it subtle so as to not overdo it.
I also like the way balsa takes detail. Next time, Try scratching up some with steel wool to put in deep weathering marks. You can use the blade to cut out minute wedges too on the ends as the timber has worn. Pretty easy. Just hard to see >_<
