How do you picture the Quantopian of the future?
I'll chip in ...
Full backtest
When done, there's a page containing all result metrics in condensed form so it can all be screen-cap-saved and/or shared.
A Save-As button saves all of that information as text AND ALONG WITH IT the backtest code AND using a default filename containing key metrics starting with returns, thus sortable locally (and alpha, beta, sharpe et. al.). You train it--tell it--what metrics you want included for those file names.
IDE
A tab next to Logs & Runtime Errors tabs says TradeInfo and one can sign up in clicking that for more detailed logging with orders & fills and cost basis and pnl (even after close and I've already written all of the code for those and more), and any of us can write plugins for it, receiving 50% of the subscription fee for each plugin.
Chart
Checkbox for the main chart to log cash, to be aware of margin, the most common exercise in mistaken exuberance.
Layout
Title box longer so it doesn't cut off long backtest titles.
Nevertheless, there's still room to move all second-row buttons up to first row for more editing area.
'Find' no longer covers the top arrow of the scrollbar.
Logging
All timestamps everywhere can be set as Eastern time.
log.info() tailorable to mere %m-%d and minute (1-390) of the trading day, for example.
Your order for 56057 shares of AKG failed to fill by the end of day and was canceled.
... shortened to:
AKG filled 45946/56057 eod cancel
"Other than that", as my 80-yr old neighbor says often, it's tough to find much to complain about.
I'm sure your ideas will include things that never crossed my mind.