How to proportionally enlarge all vectors in Illustrator?

Question

Adobe Illustrator

Given: Ai-file with many layers inside (at least 30)

Task: quickly, conveniently and proportionally increase all vector layers in the illustration.

Problem: I select all these layers, I hold down SHIFT and I want to proportionally pull at some corners. BUT Illustrator freezes (Not Responding). It looks like there are too many layers.

Question: how can I get around this problem? Are there any alternatives to this question?