Either way I've dropped SDL (would have dropped SFML as well) because it didn't really give me any advantages... All the things that it gave me were eventually rewritten by me, and I experimented with SFML and didn't like it.
So I ended up just using WinAPI for windowing instead. There is no 3D audio capabilities.
At that point, why wouldn't you just use a lightweight OpenGL context handler, like GLFW? It's designed around working with OpenGL, and it's quite modern. (even if it uses C).
GLFW essentially handles all the OpenGL code to you, and does all the context creation and handling itself.
EDIT: Of course, this is assuming you use OpenGL for 3D rendering
I don't really see how you can improve upon SFML's window class anyways, it provides everything you need really. Would actually like to see your wrapper and see what exactly you did differently.