Yzis is a vim-like editor fully rewritten from scratch based on the yzis framework. It already features multibuffer, syntax highlighting, basic vim commands.
Yzis also comes with a nice console mode application.
In Yzis, the core editing functionality is placed in a library, and interfaces are written on top of that. As of now, there are frontends for KDE and ncurses.
Especially the KDE-interface provides an easy-to-use interface for users and allows you to have tabs for different buffers and a GUI that allows you to change things like colour schemes and syntax highlighting easily, while still letting (g)vim users feel at home.
By using the powerful scripting language Lua, you can also easily extend yzis' functionality with scripts.
With an editing-engine clearly separated from the GUI, the different interfaces can be written to be closely integrated in their respective environments. The KDE frontend, kyzis, can be seamlessly embedded in KDE apps like Kdevelop.