I'm a relatively new user of Arch, but have been using Linux - mainly Debian and its derivatives - for a few years now. I would highly recommend Arch, for someone who wants to tinker and learn - Debian is too easy...
Arch gives you a basic working system, with a package manager. What more do you need? It doesn't even ship with Vim! You can choose exactly what you want and will always have the latest versions.
Furthermore, whilst hard float support is awesome in it, Raspbian is full of bloatware. I don't like
raspi-config, nor the fact it ships with code examples, which - as far as I know - aren't under package management, and therefore, cannot be easily removed and replaced if necessary. Arch will also have hard float support soon.
The only warning I have is that Arch's
python package is Python 3, not Python 2. Furthermore, using the latest packages all the time, may introduce security problems if used on an external facing box, but shouldn't be a problem on the Raspberry Pi.