FreeDOS has always been about developers coming together to write code. In that spirit, I'd like to suggest a few things I think would be great for the next release of FreeDOS.
Test games on FreeDOS and report any problems. For example, some people have problem with HIMEMX and some DOS games.
Test other DOS programs and report a bug if they don't work properly on FreeDOS (usually if the program relies on some MS-DOS feature or compatibility that might not exist in FreeDOS).
If you’ve got some programming experience
Port FreeDOS utilities to OpenWatcom C and NASM—our preferred C compiler and Assembler for FreeDOS. (Some older FreeDOS programs were probably written for Borland C or Turbo C or Microsoft C, or Microsoft ASM or Turbo ASM)
Port GNU utilities to FreeDOS, such as using IA-16 GCC (while IA-16 GCC requires a '386 or better to compile, programs compiled with IA-16 GCC run on all CPUs)
JEMMEX: Only uses first free int 15.e820 memory block. Could use largest block, or multiple blocks instead.
HIMEMX 3.34: Uses int 15.ea even where not supported. Should have support-check and some /noint15ea option.
HIMEM 3.32: Has incomplete int 15.e820 / e801 support: At least the int 15.e820 part has issues fixed in 3.34.
FDXMS: Does not insert STI windows in longer XMS copy loops, which causes hiccups in time critical drivers.
XMGR: Older versions do not use magic XMSXXXX0 name and fail to detect and work around 386SX errata. Has good memory detection. Newer XMGR are closed source.
Create a DOS package of the GNU C Compiler (GCC) that is capable of creating 16-bit DOS applications (no extender).
Add new features to FreeDOS, such as a good GPL-licensed CDROM driver.
Add CJK support, probably as a driver that uses graphics mode to display double-byte glyphs.
Write a guest tool like VMSMOUNT for VirtualBox.
Write a driver for modern sound cards.
Add some kind of UEFI bootstrap BIOS emulator, perhaps implemented as an IPL.