There are a lot of moving parts in wc3. I would start by focusing on your base build timing and positioning.
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Build burrows closer to your peon line, that way if you get harassed in 1v1 or team games, you can quickly load to defend and save workers.
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Leave only 1 or 2 clear paths into the back of your base, so you can retreat if you are attacked and let your burrows do damage.
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Build your shop near peon line/burrows. Preferably somewhere that is hard to surround and kill. Shops are important because sometimes you have to run into your base and heal, or buy TP/HP potions.