This game goes from excessively easy to super hard in a single level

Wait until you get to mission 8

i found mission 5 easy.

After the zillionth time even Mission 8 seemed rather doable... :)

What I like in this game that you can (almost) always develop a working strategy and then fine-tune it till you can complete most levels without losses.

What i find annoying is if your trying to cut down on soldier deaths, You have to press F1 just to get back to the save/load screen.