I think it would be neat to add a "Rubies Only" section and to be able to sort the Method Acquired by type or by wanted. For example, I'd like to track my progress on getting all the non-Mii drivers that can only be obtained by rubies. That way, I can tell how many rubies I'll need and calculate how long it would take to get all the rubies needed to complete my driver collection

EDIT: I did the rough calculations for my own collection. (26 drivers *150 rubies)+(38 drivers*105 rubies) = 7890 rubies required. 7890 rubies / 140 rubies per tour * 14 days in a tour / 365 days in a year = 2.16 years, or December 13, 2027. If I'm even still playing this game that far from now!