It would be really useful to have an option to buy stock as a percentage of your “Available to invest” balance.
At the moment there is only an option to enter how much cash you would like to spend on the position and you are shown the amount of shares the amount can buy.
I think for me and many other users, entering X percent as an allocation of our available balance would help with regular allocations to our portfolios and could be seen as a small workaround to the highly requested “Auto Invest / Pies”.