There's a ton of things that I can think of, but the most obvious are
- mess with our intelligence / "diplomatic" personnel. When we wanted to smack their wrist over the elections, we had a list of personnel and a couple of buildings ready to target. I'd bet my whole bankroll that they have a similar list.
- increased DDOS / other cyber attacks. I hear that they're good at the cyber.
- keep trying to use leaks to strategically sway elections / punish politicians that they don't like. You think Hillary is the only politician who could have their popularity impacted by selective leaks and / or fake news?