Once a new map starts, maybe its script is turning on the blur again? Search for setPlayerBlurLevel and resetBlurLevel if you didn't find any of these two functions inside the map script, then there's something resetting/changing the blur level on map load...
These kinds of things don't usually go to waste either way - if it gets released, there are going to be people who will use it in MTA. But letting people outside MTA community know about it would make things even better.
It could set higher standards for GTA multiplayer in general. An unfamiliar person might expect that multiplayer has the same things that single player does, except it allows multiple players to play together - seems like what you were thinking of back then, if I understand you correctly. With Sphene, that could become a standard rather than just an expectation.
An in-game editor? That's amazing! Sure, if we have a map editor that people use for purposes not limited to MTA, why not a SCM script editor as well?