An interesting read. However, some aspects that you mention don't add anything but add more fuel to the fire. E.g. Woodcutting, Smithing, Cooking, Crafting, etc. Adding custom items and objects doesn't add anything to the game. Of course, it does add more content that might be somewhat unique but that is just a matter of time before other servers take advantage of it. Take a look at Illerai, which had several custom bosses with unique mechanics. It was cool, but after a month or two there were already servers that had stolen the models and added it as a power creep. While it wasn't as good as Illerai, it still became less "fun" when other servers adapated the concept and took advantage of the available resoures.
The problem is that new concepts and ideas will alienate the players from runescape. E.g. critical hits from combat will have a big impact on PvP. If you exclude it from PvP, it will confuse the players. Why can I land critical hits in PvM but not in PvP? How does this apply to minigames, events, etc? Once again, Illerai had already added some of your ideas. E.g. Stat reduction, bleeding, parrying hits, toxicity, etc were all added to the game. Did players like it? Yes and no. PvP players hated it, and PvMers were somewhat neutral. They liked the addition of new mechanics, but didn't like the fact that they had to spend time to learn something which wouldn't be applicable anywhere else.
In other words, while some of your ideas are good - No one is going to use them, just like your map. The RSPS scene really isn't a place to be innovative when it comes to game mechanics as the targeted audience actually prefers power creep. See Reddit, RS3, OSRS, and more or less all RSPS that have a take on it. You'd be better off dedicating time and resources to a game outside of Runescape. A new MMORPG, or a new game in development always love these takes and would be more willing to add them in comparison to the RS community.