udev? The best alternative is not to use it. And by learning how to not use it Linux and the *NIX world will begin to make more logical sense.
The best long-term alternative is to use static devices (see note). If you've got the driver, the Linux kernel manages hot-plugging. I prefer not having udevd running, ever.
dbus is another matter. It does slow down your system but, the ever-changing world of script folks love it. So, a lot of things, you're used to, like web-browsers or applications with script-backends, have to be fixed (launched or rebuilt without that stuff or dumped for another application).
Note: If you're just plugging in a flash drive or dvd device, use
dmesg|tail to see the name of the device to mount. Learning when a device is a character or block device is fundamental system knowledge in the world of computer hardware. In Linux it's open source, check this out a lot about Linux, not just embedded. It's the best for a broader understanding the straight forward logic (not philosophy) of all *NIXs, like Linux (Solaris, HPUX, AIX, etc).
Udev, dbus, gconf/dconf, systemd, gnome-shell, Gnome, Glib, mono and Fedora are for people with loads of time on their hands who can't RTFM, or wanting an automatically updated really slick (looking) but, slower than molasses, buggy, half-way-there Linux. (A truly awful place, look around the web for tons of similar experiences).
The system boots then runs udevd. But, it's claimed udev is necessary because, device minor numbers
will change on reboot. Udev's raison d'etre seems to contradict itself at every turn. And where it's files are seems always wrong no matter who you consult. Don't trust or freedesktop.org.
Besides udev is being absorbed into that horror known as systemd, I don't know what one does with ones /etc/udev junk then. And, it is fatuous to say that writing udev rules is somehow better than anything. The gentoo folks seem to want to hang onto it and not have to have systemd, so they've forked it to eudev.
If you want a ridiculously fast, no nasty suprises system, use the Linux basics.