I used InDesign’s Data Merge; I scripted on top of that to add functionality Data Merge didn’t have.
The Illustrator variables seem interesting. I remember that I actually started with Illustrator, but had to move towards InDesign for some reasons (I think vertical text centering was one…). Also, Illustrator just seems volatile and really does crash my entire computer like it’s Windows 3.1. But I’ll check it out again next time!