Kindle Fire's actual name on the ADB Devices List Not user-friendly
What makes this easy is using tab-completion to complete the device ID. Type

adb -s D0


and press Tab. The plugin in your shell will run adb devices to find the full device ID and complete it on the command line for you. You can then type in the rest of the command.

adb is a tool for developers, and even developers don't usually run it by hand from the command-line: both the main Android development environments (Eclipse-based and IntelliJ IDEA-based) have GUI wrappers. There's not really a need for it to be any more user-friendly than it is.