I recently had a chance to learn a tune "Kealohi" from Kawika Kahiapo that he originally recorded with Milton Lau on "New Wave Natives" a bunch of years ago. It's in an open A tuning (EAC#EAE)that he learned from Gabby many years ago. I'd like to do more in this tuning. I'm exploring some of the chord forms, but I could use some help if anyone has done anything in this tuning (home videos, Youtube, suggestions etc). Kawika mentioned that Gabby used this tuning frequently (actually I think Kawika said Gabby played it a 1/2 step up in Bb; that's a little too string tight for my GC7). I'm hoping Uncle C reads this.
A couple of years ago, I put together a slack key tunings manual for a workshop, and the A tuning was one of those that I included in the manual. It's a great tuning, and I'm surprised it hasn't become more popular over time. I pulled the A Tuning chapter out of the manual, along with a page containing a few turnarounds, and posted them at http://www.imtcorp.com/workshop/A_Tuning.pdf and http://www.imtcorp.com/workshop/A_Turnarounds.pdf . Let me know if you have any questions about reading the chord charts.
I been using this tuning lately. Teachin my Kani Ka Pila boys how to play in A. It's also good on a Baratone Guitar. Tuned to the key of A by using my C tuning. Let me know if you have any questions on this.