Quick Little Update : Notepad++ is Magic.
Slogging through the cutie marks and class update now, i think there's around 650 different cutie marks split into several categories then spread across the different classes, this makes adding more cutie marks much simpler. Doing a much bigger change than I initially planned with the classes this time around. Classes now affect more than just skills, most of them also changes personality tags a bit, and some affect stat gains and caps. Of course this does result in quite a lot of work that needs to be done. I have thus far completed the pegasus skillset and the pegasus and unicorn cutie mark lists. Hoping to get around to doing the unicorn caste list today, but at the very least I should be able to finish the cutie mark definitions.
The file size is maintained around 11-12Mb, so not as bad as I initially thought, even with a much higher volume of caste options.
Lastly, I had a look using dwarf therapist, and as was mentioned earlier in the thread, yes, therapist uses the name of the caste for its grouping, so all unicorns and earth pony castes are grouped together... BONUS!
As i mentioned before you won't be able to see exactly what your pony is good at, this is primarily done to prevent even more shoehorning than is already rampant in DF. I don't want people atomsmashing ponies because their special talent is modeling and not blacksmithing. They'll still be just as useful as any other non-blacksmith pony at blacksmithing. Well.. until you take the race into account ofcourse.
I am also looking into implementation of the elements of harmony interactions, should be fun if they work!