I did not understand first question. Yes mercenary changes is at 1.5.8
By the way something can be annoying for player and can be also related to snowballing (long term side effect) is sometimes parties around enemy cannot catch it even they should :
Here normally weak and fast parties should catch 733 men Khuzait army. Black numbers are speed of parties. However 82 men Empire party come close to Khuzait army and run away back because it thinks 1208 men army cannot join battle (can be out of radius at first moment but it will catch up). This behavior saves Khuzait army from that bad situation. You can see how Khuzait army is fast (3.4 vs 1.9 (forest and bigger army disadvantages are effective also)) compared to Empire one because of horses it carry and better cavalry ratio it has. But even this speed advantage here weak & fast parties should catch Khuzait party and it should not escape from this situation. I will examine it and think about improvements. Something valueable can be found from here to improve gameplay & kingdom balance.