Maybe do some sort of Dev package, where alle those tools are collected.
MOS, AOS and AROS.
Maybe do some sort of proggy, that can help with development, ie. some sort of visual tool for GUI, (could generate C code). Have a look at RapidQ for Windows, this is how things should be done, IMHO.
Just use C instead of basic
Other Libs could be a standard, and easy to use, lib to handle different soundformats, pictureformats and anims.
While we are at it, some basic 3D stuff, that uses OpenGL, but adds some more, and easy to use functions, such as texture blending, different effects, (fire, water etc.)