Leaning towards Balance K Omega with Cone for the string tension off the nut. Nice direct lines . I have crown ones and the angles aren't as pleasing to the eye. I imaging there are some vibration issues too.
Way to go Danno! Everybody should own a Series instrument, and some more than others.
For a 6 string I think Susan and Mica suggest a Knobby headstock, as the low B on a Crown 6 usually sits a little too close to the nut so you wind up with part of fattest part of the string on the post. On mine, we moved the tuners a little away from the nut, and we moved the tailpiece a little towards the point, so the B string winds much the same as the others. On a long scale with an Omega cut-out that might be a tight fit, but on a medium scale you might just get away with it.
Here's a post showing both ends of that bass.