Your idea on statistics is fantastic, awesome and brilliant!
A few things that are still lacking there though, making the statistics tool a lot less useful than it could be:
Be able to cross-show the category across multiple accounts; This is super-important!
I think this is very basic and perfectly justified, the majority of “power users” will use more than one account to escape weekend markups etc.
More detailed filters on the list, allowing for custom time range filtering.
Custom categories or tags; look at Polish mBank as an example. A lot easier to make use of statistics if you can create a custom tag and then report by it.