It is convention on the wiki to color changes to relationship points in green or red text, but it's been proposed that this should extend to any mention of a specific RP threshold or value as well.
Personally, I believe it's better to keep it as changes only. Green and red text are also sometimes used for changes to flags, like the Yhilin battle guide, and for page size changes in Special:RecentChanges, so I think a convention of using these colors specifically for changes has evolved. I also feel there is a danger of using too much green or red and diluting the reader's attention.
However, that is my opinion. This is a subjective matter that deserves community input, hence this thread.