Great strategy to do in 2v2 with a zerg is to go Reaper and Zergling ( with metabolic boost )
You can easily outmass your opponents first teir units, and it's a great over all strategy. If you keep pushing it though, remember to tech out incase it fails.
TIP: Whether you decide to proxy or not, you must always get nitro boost. Don't save that extra 50 mins / 50 gas for 2nd reaper, Nitro Boost will help you out 100x more in the end.