Good day, First of all, I try to get GNOME 2 to work solely for fun. Just because it's offered. I have a (precisely) working Xfce desktop on another installation.
Second, I dislike dbus as much as you do. We usually compare it to systemd, because most of desktop packages depend on it, but it is useless pretty much all the time. And what's even worse, dbus starting from Debian Jessie, now depends on systemd, well, that's another issue. Third, there is no dbus script, and as I said, I've made my own, something copied from Linux From Scratch book. Point me, if there is a startup dbus script somewhere but I have 10 binaries with dbus name in /usr/pkg/bin and that's all. Fourth, login and shutdown issues are likely to be ConsoleKit/PolicyKit issues. In Slackware, for example, there is a consolekit script in rc.d. In my Devuan installation we had to make a couple of configuration files for polkit. Fifth, I wouldn't say GNOME2 is something really big, comparing to GNOME3 and KDE3/4/5, but sure it's cumbersome comparing to window managers. And the last thing, GNOME2 here works fine, with a couple of metacity issues, and that shutdown/reboot issue that I've already mentioned. Mitt PS Why does it take around twelve hours to get my emails delivered?