FlowGraph, which is the main thing used to build story in Vn Engine, is much more dynamic. Vinoma is very linear and you have probably noticed how hard it can be to branch based on player choices and other variables.
The only things missing from Vn Engine (that Vinoma has) currently is saving (being implemented this week), Log and the hotspots overlay (all of which will be added). It already has more options in other areas, like image overlays, and more options when building logic for the flow of the story via FlowGraph nodes present in in BGS core system.
Check out the videos. It is probably the best way to see how it is used and whether it might be a workflow that will benefit or include features you can use. https://www.youtube.com/playlist?list=PLuaBtUXEKcdK9UtD8rx3tYMfLzPRawwOV