Well unless you are playing like in GM level, you can do just fine with around 70 APM.
APM is not a measure of skill... When you look at SC pros spamming clicks like crazy , it's not because they are actually doing something with them, most of the clicks are overall just empty hits that do nothing, but it keeps them warmed up so in the case that they do need to micro something, they can do it faster than other people.
I have a hard time beliving you wont miss scvs or marine cycles if you are not constantly tapping your production which will lead to 100+ apm easily... and you simply cant afford to miss production cycles if you ever want to get into masters.