We don't create a separate group for each user. The system admin can do so if he likes of course, but the system defaults are set up to create the home directory, and put the user into group 100 (users).
We use dash as the system shell. While bash is installed as part of a base install, using dash helps us keep the system scripts simpler and more portable.
We use mdev and the kernel hotplug interface, rather than a dedicated daemon like udev. In general, hardware is not added all that frequently to a server system, and the extra milliseconds it might take to run a separate program is worth the increased transparency and robustness of the system.