There is compelling cost saving marketing strategies made by Microsoft for companies to think about migrating to SharePoint online. No need for data centres and flexible licensing being the strongest reasons. But as of today is it practical? Security is the biggest concerns of enterprises but does the online product support features that are required to move organizations to SharePoint online. Let's see below.

Apart from any customizations, as on today SharePoint Enterprise online does not support the following features -

General Features -
Insights Features not available -
Search Features not available -
With so many features unavailable, only plain, vanilla out of box installations can be moved to SharePoint online which will be very limited enterprises, probably just small and medium sector organizations or simple websites. Lot of features need to be available to move the entire data corpus to SharePoint online.