Only for attacking. I were killing units first and attaching cities second. After I attacked a city 20 times from one of my cities, siege units got 200% bonus to attack, which gives 3x more damage alone. In combination with +25% attack bonus from Autocracy and bonus from War Games resolution, every city went down in 1-2 turns. The specialist bonuses were ok, I have worked all scientist and some enginners. However other bonuses to science might be too much. In Medieval era Russia has 10 techs more than me, but I was able to get ahead of them, despite the fact that I went Imperialism/Autocracy and they went Rationalism/Order. It wouldn't change anything for me. I had plenty of oil thanks to Autocracy, CS alliances and my territory. Also late game I had permanent 40% bonus production from conquest and was almost always sitting at max supply cap. Also I had zealotry. Why have you decided to give SPADs logistic in the first place? To have synergy with UA?