My Suggestion:
I believe spoiler tags should be incorporated. Spoiler Tags are used to hide lots of texts or images until you click the "show" button. In which case all the text/images are revealed until you click the "hide" button.
Why and what benefits this function provides:
This would be very beneficial when it comes to organizing a long post. (Examples: Long trading lists in which you normally only see the Words Armors, Weapons, etc. with a spoiler tag under each Category. Or it could be used in the Graphic Request forum when someone requests more than one signature. You would just see something like. Spiderman Sig, Superman Sig, Green Lantern Sig, etc with a spoiler tag under each giving more info on what is desired.) I believe I got the point across on what Spoiler tags do and how they are useful, but also I believe it could bring the removal of the no more than 3 images a post rule. Maybe the rule could be something like only 3 images outside of a spoiler tag and only 3 images inside of each spoiler tag. I'm not sure if that is possible to enforce but it is an idea

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Anyone who doesn't understand a spoiler tag here are some images:

