I have to confess that I have a platform addiction ¯\_(ツ)_/¯
But I finally stuck with MotiveWave, so much so that I actually paid for a full license even though there are a bunch of great free platforms. Main thing, works on Linux and macOS, where as many other platforms are exclusive Windows.
Also, the SDK is quite nice too!
As for commodities, I've found some success in agricultural commodities but I also dabble in currencies and indexes. Agricultural though have some interesting characteristics given than they have an actual physical thing behind them as opposed to how stocks move... which varies depending on which side of the bed the CEO of the company woke up!