Hmmm. I usually have 3 Heavy Assault Battalions go with the Xeno Team and the Engineer Brigade, just in case.
I have high ground combat tech because, no matter what I'm researching, a group of labs is always researching
ground combat. I like to capture alien homeworlds intact because, they REALLY boost your tax base once they become
Imperial Populations. Also, Precurser Robot Soldiers are flies to be swatted, if your ground combat tech is high.
Eric