This is really neat.
I had a conlang phase when I went through college. I never finished it, but I had like 90% of basic grammar rules done for a language tailored to a race of fire breathers...thinkin about it, I need to pick that project up again and finish it one day.
I thought about making a conlang for Equestrian ponies, and if I did, it'd probably include:
Gender inflections for different kinds of foods. Greens vs. Sweets.
Varying levels of plolite ness. Please and Pretty please with cherries on top, could be expressed in affixes attached to verbs.
Word order would probably just be SVO, and the language would be fusional. As for phonemes and phonotactics, I never got that far into it, but there's room for experimentation, especially if we want to implement 'whinneys'.