I've recently noticed that with my Illustrator documents that I import into After Effects, I cannot see the layers show up for like 20-30 seconds upon after the import; the screen is completely black. I wanted to make sure that this wasn't a software bug or it's just After Effects trying to process the big Illustrator file. The files that I've been importing are in the size range of 40 mb - 60 mb with about 15-20 layers in each document being imported.
Error or problem, FAQ, How to, Performance, User interface or workspaces
Lunchtime (edit - love voice to text) Launch Time depends on the number of vertices on the layers, not the total number of layers. Some very complex AI files with thousands of vertices may not even open. Check your AI file for complexity and simplify as much as you can.