Some news about the progress of decreasing the dependencies. I successfully replaced the SDL_Image component with the Vampyre Imaging Library. This means we can get rid of the following DLLs on Windows: SDL_image.dll, libpng12-0.dll, libtiff-3.dll, jpeg.dll and zlib1.dll.
I am thinking about removing the support for Truetypefonts since they aren't retro, are they? This would save two more libraries: SDL_ttf.dll and libfreetype-6.dll. Because we have the built-in font and it's possible to load bitmap fonts this is no problem.