Honestly being able to have voice coms with a mate makes such a difference. For instance the time it takes you to type something you could have been doing something else.
Every RTS ive played ive never used voice and been pretty high rank.
I think dow 1 was the last time i used a mic but it was because there was loads of us on it at once.
My current allie is German and my other friend is Croatian, so mics would actually hinder us imo.
Only words i type really are gg or omfg dropper allie/AFK allie xD