I read a lot of stuff that didn't help me at all. Masters isn't full of that many people, so I figured a lot of the advice online was from lower level people anyway. Then again everyone is different.

Watching noregret stream was amazing. I actually didn't know anything about him until a week or two ago. His ling bane micro is insane, and he went like 15-0 in zvz in a stream. He doesn't hotkey his units, though. That immediately kept me from stressing out about worrying about perfect unit control and hotkeying all my spellcasters. It literally doesn't matter at all for getting into masters.

I actually started doing better when I used my all army hotkey because it kept me from having idle military on the map during crucial fights. I even find it easier to select all army the a-move and then catch the lings on the towers and by their future third or fourth expo's and just rehotkey them and move them back to the tower or stand ground to deny their expo. I have control+1-9 as my steal hotkeys by default, but you can setup just one hotkey to be a steal hotkey if you want so you can just control+2 a unit or more out and have it stolen from your main army hotkey. Anyway, what I'm saying is that I actually started using the all army hotkey more as I got better, but I started it WoL and it took me a bit to even get used to having the key.