Libra's stronger than they imply, and her deploy is not useless. Considering how she's the fastest, and good players can micro with her against approaching targets, she can prove to be amazing. Back to the deploy ability, if you see some lonely non-Soviet Miners, sneak up on em and skillfully use the deploy ability and hopefully be able to destroy em (You can get away with fighting 1 War miner). See a lot of anti-armor units that don't hurt infantry well like Zephyrs that are poorly defended? Rush in and deploy. Someone trying to escape with an undeployed MCV? Let Libra flip it over to its death with her ability again. And if you have a partner who's China, EMP + Libra deploy combo on armored units (not escorted by anti-infantry of course) is amazing. You can even use Shadow Ring so that the opponent must rely on detectors or sound to find her rather than the radar.
Unfortunately, watch out for Siegfried and especially Magnetrons, not to mention Morales can 2-hit KO her.
Oh, Yunru, cute little Yunru. She's good for support, yes, but she doesn't always have to be inside the Centurion to be great. Sometimes you can sub her for 2 more Eradicators for the Cent (watch out for robots/Radiation immune units) or something. Remember Yunru can move faster than the Centurion. And her Earth Breaker? I got 2 words for that: "Yunru Combo." Those who seen me on the stream using China will get an idea on how it works. Use Dragonflies and put em near enemy radar to temporarily disable their minimap sight.
It takes a while to kill the Conyard, but try to go for the factory, barracks, or refinery, generally fragile buildings. Just try not to do it against well-defended bases. Even a T1 defense or Terror Drone will ruin this. Don't underestimate the true power of Yunie-chan. Some have suffered seismic activity in their bases, often leading to their defeats. After all, "Knowledge is power."