[Sensori]

If you want to use scout decoys, yep, they have to move with the army. Although I think it's not worth your time getting them and using them - it's useless unless they can be in some way useful in actual fights. Hell, for that effect, I just have a crapload of Star Children moving with my army which seem to be preferred targets for your attacks - with full research, they aren't really worth anything to me anymore, other than as a bit more expensive than regular Illithid Mind Blasters.

So, your main problem is that you don't have any cheap commanders which actually would still be worth something in a fight as well, but are expendable enough, too. If you start putting items on them they become better in battles, sure, but then it'll actually sting when you lose them... Which makes it less nice, and not really a good choice when you could put the items on your mages which need the protection a whole lot more.