The wallet should have some sort of way to compile all your transactions into a single space. It could summarize each transaction with how much was sent, how much was received, any fees associated and the date the transaction took place. This would be immensely helpful during tax season.
This could come in a number of forms, but I am unsure of the work needed to provide this. It would be great if that transaction history could be exported out of your wallet and either downloaded to your computer or sent to your email. Finally, it could include any dapp transactions, such as pool-together or rari.
Not sure if I am missing something, but let me know what you think!