It seems like the merger is only in name right now. Corona Render immediately benefited from their merger with Chaos, but then again V-Ray and Corona were somewhat similar, so I'd say it was easier for Chaos software engineers to help Corona with things and implementations to make the two engines more compatible (or rather Corona more compatible with V-Ray, as V-Ray was way more advanced at the time of the merger).
Enscape UI designers can only learn from Chaos's UI experience, which is tremendous and spanning through so many software packages that you can easily lose count.
Twinmotion follows the trend of "early access" games, where amateur software developers come together to develop a rendering engine (only they don't write much, as it's all on the back of giants, in that case Unreal Engine). What's bad is that it tries to simplify the UI for everyone, but that kills any features that make render engines powerful. Simplicity is good but not at the expense of cutting short features and important tools. Many other software packages, be it Blender or other seemingly popular render engines like D5 Render, always seem intuitive and cool, but once tried by a veteran user, there are fundamental tools that are omitted (usually due to ignorance of the developers or convoluted roadmaps) that makes the software nearly useless if not counterintuitive (for the veteran user that is).
My wish for Enscape is give us more frequent updates than we currently get, have a robust roadmap that lets us know what we will receive every 1-2-3 months, and a future goal that says Chaos will help with the software development in order to make Enscape more comparable with the tools that Corona and V-Ray have.