If you use a naming convention where branches and tags are grouped using the standard directory separator, slash or '/', they cannot be linked to by their name, but must be linked to using the hexadecimal checksum identifier.
On a slightly related note, it would be nice if those groupings where combined to a hierarchy in the web UI. I use BitBucket for hosting full-history mirrors of some LLVM repositories, and the numerous Apple version tags clutter the list.
Other than those minor issues, I must say that I find your services to be excellent and very reasonably priced. Thank you, and I hope you enjoy the holidays!