I'd say it was similar to xmonad in spirit, but with instead 2 or 3 specialized DSL, for:
- keyboard shortcuts
- menus
- windows
- workspaces
I can't remember others. I'd say there were 4 parts in the configuration.
And you'd plug things for access bar. But with time I even dropped the access bar 
Then I went for xmonad, which I really liked. Both #fluxbox and #xmonad made me adopt a workspace+terminal centered workflow. Now that I have the habit, the default gnome install suffice me. But it was forged in fluxbox/xmonad daily practice.
It is important for me: it's mostly because of the perfect aesthetics that I switched to Linux entirely -> I could have MY OWN totally my OWN desktop
This after a 100th windows update failing in the middle and n-th time leaving my system broken: the time too much -> not wanting to reinstall everything
The user screen desktop that made me choose fluxbox/openbox was based on this: with menu and buttons in the same shade
I worked facing a zen ocean with transparent terminals
The contrast with Microsoft VIsual Studio is without comparison possible