2 (in no particular order)
5 * Handle glInterleavedArrays correctly.
7 * Allow clamping to a GL version or a number of extensions.
9 * Match the traced visuals (which will imply abandoning GLUT)
11 * Trace multiple threads
12 * GetCurrentThreadId()
15 * Put zlib (de)compression in a separate thread.
19 * Retrace multiple threads (which will imply abandoning GLUT)
21 * Provide a readline-like interactive mode to gltrace
22 * http://github.com/antirez/linenoise
23 * https://github.com/antirez/linenoise/issues#issue/8
24 * http://hg.youterm.com/radare/file/87579f8c5087/src/dietline.c
26 * Trace window sizes somehow