Its not actually a balancing thing, but I think it fits in here better than in the bug report section.
I had an idea yesterday: how about making engis and the acu walk/drive through t1 pgs, as they often walk/drive 5 times around a pg, or get stuck, or need hours to do what you actually told them for whatever reason.
The only problem imo is that you maybe could hide engis in pgs then.