Have you thought about canned L/D?
I think it is great to be so particular about what foods she gets but I think she also needs to eat something she likes or she may just start refusing food altogether. I also know that when you start talking about vegetarian protein, low purines, etc., the selection of food is very limited.
The RC LS 14 is very palatable also (if she doesn't rip her ears off scratching from the stuff
). Have you looked into that or are you staying with the NB?