I think we discussed this on the US steel forum but I went with an Eb tuning based on the same intervals you used on your wordpress site for the 12 string leaving off the two bottom strings. So essentially a 10 string version of Eb13: Eb-F#-A-B-C#-Eb-F#A-B-C#
No downside for me. It seems quite natural and covers a lot of range IMO. Of course I play with jazz/improv guys most of the time.