There are about 1200 or so unique (includes all tones) Mandarin Chinese syllables, according to some source I read a while back based off the Unihan database.
For my applications I'm limited to using only 1/3 of those 1200 syllables, but I do realize that there are a fair amount of obscure syllables that are hardly used in normal conversations. The problem is, how much of that 1200 is obscure and not so useful? How would being limited to using only 1/3 of it limit my speech? Would I be conversational? Or brought to the level of a grade schooler? Or even worse, unable to hold any sort of conversation?