just depends who the covy leader is in 1v1.

Vs. Brute i would start with wraiths, hard to vortex them with the heavy shield upgrade and they just stomp the chieftain with small micro. if he has a hall, i would dispose of the factory and build banshees, they are a bit fragile to vortex so just keep away and pound the base. imo HGs arent really worth the money. and cleanse beam only counter units, the leaders have a bit too much health for an un-upgraded beam. the beam is more of a quick counter to thier counters, well thats how i use it anyways in rushes, it saves alot of money.

Vs Arbiter yea hes just annoying so i cant really say much there. he really hurts on money used from rage b4 he gets the 500 rage upgrade. so you have to rush him before he gets there, or you're basically screwed. mostly me plan would b is focus on leader upgrade over power upgrade against arbiter for early rush. his money wont support enough to kill u all the way w/o him taking massive damage. just bring a couple of trash units along to distract him from your leader so u can pound in a few shots. if you see he has the health upgrade then just stop sending units and focus on the leader ups. just attack early and force him into using his rage alot. don't use your beam on him. a good rush against an arbiter is to cripple him if you cant kill him. just make sure u recall before ur shields go away and resend him back to his base once you recall so hes always raging or spending money on weak counters.