Let me clear all this bullshit about exposure and powers up:
Where the abilities come from: They only get superkryptonian abilities from exposure to a young star (yellow, and presumably, blue/whatever color gives the super powers in the comics). Even on board Black Zero they had them. Evidence: Exhibit A: Kryptonians were being shot by Lois (with the same gun that killed a council member earlier) and hit hard by doors, yet they were fine later.
The Armor: The armor limits little, if any exposure to solar radiation. It's the mask that is the key to them being limited. The mask keeps them breathing an artificial version of native Kryptonian atmosphere, which is "less nourishing" than Earth's. Essentially: Krypton's harsh air inhibits super powers, whereas Earth's nurtures them. Evidence: Exhibit A: Kal-EL being weaker/completely depowered around kryptonian atmosphere, because he wasn't used to it. Exhibit B: Zod's initial exposure to our atmosphere left him overwhelmed by heightened senses that seemed to be activating on their own. It is easier to go from Krypton to Earth than vice versa. The native Kryptonians were not inhibited by their atmosphere simply because they had adapted to it. When Zod discarded his mask and mentally managed his exposure to our atmosphere, our air immediately began to nurture two underdeveloped abilities: heat vision and flight.
Kal-El's prolonged exposure: It is true that Kal was absorbing solar radiation for longer than the others, and it is likely due to that that he possesses such a physique despite likely doing no exercise or pushing himself, and his ability to fight them despite being untrained (he was more familiar his abilities). However, it is flawed to think that longer exposure automatically = more power. A Kryptonian's body, as I understand it, is like a solar battery. After a while a battery simply cannot be safely charged any further (sans sun-dipping, which we don't even know if MoS Kal is capable of yet). Zod's soldiers were within Earth's orbit for at least 20 hours before Faora took custody of Kal. They were being charged this entire time. It is reasonable to assume they were approaching Kal's level of pound-for-pound strength and speed this entire time, even under their atmosphere.