Forgive me for not noticing this thread earlier. When I see "Mac" issues, I tend to stop because I9;m Windows. However, when I see Eboni-6 I usually do try to see what is going on, and I didn't see that before I stopped reading.
> ... I'm still having solarization problems ...
>The head alignment and nozzle checks are excellent, the ink pattern page that prints now is for all intents and purposes absolutely identical to one printed when I wasn't having the problem, ...
> Epson Artisan 1430 with the Eboni6 inkset.
There is a possibility that the printer is bad.
Try printing with the Epson driver set to Color Controls, gamma 2.2. That driver is very tolerant of minor ink mixing errors and would cut out QTR and profiles as variables.
Paul