I agree with the comments you've gotten so far, the question is a little open-ended.
But in the spirit of helping -
I use the Gantt chart to give me a visual representation of things that haven't happened yet. I can look at it and see the flow of the project - when things are scheduled to be done, how tasks/deliverables relate to each other (dependencies), where resources are scheduled at any given time (on not yet scheduled), important dates (milestones).
The Gantt is where all of the pieces of the project are displayed collectively. Outside of this visual aid, I have to look into various docs for information - into contracts to see when a vendor is supposed to deliver something, or when subcontractor is due to start, emails for new dates or resource issues, etc.
It also gives me a place to see the overall project (at least in terms of deliverables. My contract may have the scope and deliverables written down, but that will undoubtably take several pages. The Gantt allows me to list it all in one long list, and then view it as I need to - roll up to milestones only, a specific deliverable, print it out and hang the whole thing on the wall so I can see it all at once.
To be honest, I'm not sure how a s/w package could 'analyze' this in a way that I would find useful, but I'd like to hear how you're going about it.