What Metrics, Charts, Graphs, or Data do you want to track on BlitzMemory.com?

We want users to be able to track their progress on BlitzMemory.com. So I would love to hear your ideas on what kind of things you want to be able to track! What metrics? Also, what form do you want the progress to be tracked in? Like charts, graphs, tables, or some other forms.

I personally love tracking my stats and progress because it helps pump me up and get excited to see how far I can go! I would greatly appreciate any ideas you share with me!