My currently pending changes for Haiku:
- custom baudrates support in serial port drivers (I need it for high speed communication over usb serial with my Amstrad CPC)
- improvement to ps/2 mouse-touchpad multiplexing detection (my laptop keyboard controller advertises support for it, but doesn't implement it correctly)
- automatic enabling of VESA BIOS live patching to inject custom video modes in video cards BIOS
1990s technologies don't want to disappear from modern hardware!