Sounds cool, though I’m a bit confused as to why that is such a big priority given that ReactOS currently aims to replicate Windows NT 5.2 (XP x64 / Server 2003), which did not provide graphical set-up*…
Technically all Windows versions up until, IIRC, Vista had their install process in two stages: a text-based stage where you’d input the most basic info (what filesystem to install onto, what Windows directory to use, etc.) and a graphical stage once the basic files are installed (where you’d be asked what devices the computer has, whether it’s networked, date/time, etc.). From Vista to the present day, the first stage is graphical as well. ReactOS’ latest release uses the pre-Vista model, but the latest blog posts indicate a move to the more modern one.