In latest Haiku release (nightly) most of config files are a species of binary format,
(for example ~/config/settings/ScreenSaver_settings).
As haiku is not BeOS, and as it is free and opensource, why not having all config files in plain text?
note : For R1 with legacy BeOS support this cannot be an easy task.
But it can be done for R2 (BeOS will then be run in emulation mode, and some translation of files can be done).
eanyx
As the most of the files use a Flatterned BMessage…
Wich results in a binary settings file…
The easyiest way would be to write a simple Editor for a flatterned BMessage…
This isnt a too complexe task… from what i remember 
Actually, we have the introduction of some JSON to BMessage parsing helper classes just recently (still a private API currently), so it might be possible to start flattening to JSON instead of the current binary format.