The RTS sections are, unfortunately, not very good. Generally, what I found I needed to do was let enough units build up in one area that I could then do an overwhelming push towards the next objective. Eventually you get enough of a snowball momentum to get things going.

You also need to fly around and spam face melter like a madman. That is your bread and butter and the main way you’ll be keeping enemy unit count down. Trying to win army vs army fights tends to go very badly unless you are directly intervening to make sure the fight ends QUICKLY.