Exploit you need to put some thought into how you use roaches. They're a great unit, but you can't just run them at stuff. You need to deliver them, whether that be by using them as a mine, by disarming people first, by dropping them, or by cloaking them.

I think it's a bad idea to have them as just part of your queue. They're an inherently reactive unit unless you can prevent your opponent from interacting with them. When you see a good point to make a roach trap then sure, make one and put it there, but building roaches periodically regardless of their value is just gonna cost you metal and APM.