How much lore can be altered, and how much should stay as it is?
No lore should be altered.
With all the changes Discovery has made, though, it precludes the idea that particular avenues should be closed to factions in the expansion of roleplay and lore. To bind yourself into a narrow line of thought and prevent any sort of derailment from that by saying "You can't, we're neutral," isn't roleplay in any way, shape, or form, and it isn't much fun for anyone. Are the Zoners politicians or not? When roleplaying as a Zoner, do you have to balance politics, or not? Nobody will roleplay a Zoner if they don't have to... which means, if you cement the idea that they're neutral, and nobody has to work for that, you're effectively changing Zoner roleplay into something completely different.