Few things I feel can be improved are:
  1. Ability to purchase on number of units - rather than dollar value and portal calculating how many units it will approximately be.
  2. Ability to view market depth to some extend, e.g. 3, 5, 8, 10 layers will be good.
  3. Ability to set an order expiry date – instead of active until cancelled or expired
  4. Ability to amend pending/partially filled orders after placing them
  5. A breakdown of what the order costs just before placing it: $123 + brokerage $6.50 = Total (balance funds available: $....)
I think those are some useful features that will improve the user experience, thanks!