There is always the 'mook' route. If this enemy is super high tech, there is a good change most of the people don't know how to use it, take care of it, or even be decent with it. With ascension comes hubris.
You could just say that they believe the tech is SO GOOD, it doesn't matter who they put in it, even a military draft of the poor. And not being skilled with certain tech brings its own penalties, which the PCs can use with lightning attacks to swiftly overcome those weaknesses. You should adjust the skill of the enemy including the army alongside the PCs, so it evens out better.
This also points out morale. The best armor in the world can't help a green soldier who buckles and runs under a surprise attack. Use these things to your PCs advantage, maybe even alongside a tweaked Stormtrooper Armor idea.
Remember, the game is about the players, so make any changes you need to help them enjoy the game.
Edit: On the poor idea, a culture so steeped in tech and superscience will most likely shun those who are weak, dumb, old, young, etc.. Racial extremes for them that aren't intelligent or strong would likely be the first stuffed into the armor and sent out.