Currently you can see the value change in bitcoin in the last 24h, I assume is a lineal chart, what about a week, a month, a year, the whole life of the coin or logaritmics charts and the ability to switch between them.
Also the chart express the change only in the wallet selected fiat coin, why not allow to select which fiat coin is used without changing the wallet coin.
Another important thing is to know which exchange (the source) of the chart, even for bitcoin values vary signifcantly depending on the house doing the change (I assume is one of the 2 official ones now: Ramp or Banxa providing this chart, right now is impossible to know which one is providing the data), the ability to select between diferent exchanges will be nice to have too.