I have found a few documents about new features in SharePoint 2016 on premise, but I can't find anything about SharePoint 2016 online version. Especially I am interested in BI part. Do you know any resources about this or about do you know Microsoft plans according SharPoint online new release?
As Wjervis mention, features that are new in SharePoint 2016 On premise has been and are being deployed and you might be using them right now.
However, Microsoft pushes out new features to servers, not tenants so there is no guarantee that you have access to anything new yet. And there is always a chance that features that will make it to on premise won't be available to O365 and the other way around.
The best place for what new features that are being implemented in Office 365 is found on their roadmap.