Extended notes only works on beneficial group buff songs actually. The range is real small yes. In a group, you can use it for crowd control and for memblur. I'll usually turn on attack to offtank it during the cast time so it doesn't go after a healer. It memblurs the mob when you break charm at the end and will only have you on the hate list, so be ready for that.
For kiting, the most common technique with the short range charms is to mez it first, then charm it while it's mezzed, usually just before mez is about to wear off. If you're swarm kiting, you'll want to mez it and run the swarm away, then run back and charm just before mez wears off. Takes a little practice, especially to get the timing down, but that's how charm works now. Also, the range of it is just a tiny bit out of melee range, so if you don't mind risking a few hits, you can kind of duck in and out of range to make it land, but it's definitely tricky that way. You only have to be in range at the start of the song, and when the song lands.