Movin' this thread to the Game Opinions & Ideas child board.
As for the topic itself, I see a few pros 'n cons with this idea.
I will agree that by makin' downloadable mods like items, markings, etc automatically coded into the game will aid some users who may not be used to downloadin' add-ons or know not on how to do it altogether. In fact, doin' somethin' as such can make things a bit easier. I see where ye' get the gist of this idea and the simple benefit it upholds.
However, keep in mind that not everyone wishes for their creation(s) to be made public. This mainly goes with content like maps, textures, items, etc. Things of that sort. I'd agree with this idea if it allowed users to choose whether or not they'd allow their creations to be coded into the game for all to see and/or use but I see not a sentence that speaks that (unless I've misread). Which is why I'm more so leanin' on the reject. It'd be wrong to immediately, without permission, make every downloadable mod open for the public. There are certain personal items users wear that no one else has access to, textures some use that they keep to themselves or share with only close friends (one such texture is my moon mod for example), and of course we all have heard about private maps- more often used for private role-plays in the game. I foresee that if this was to be pulled through, while some users may be ecstatic about it, those who were usin' said private creations might become a bit offended.
Also, another con is if this were to happen, it could threateningly overload the game entirely. If ye' consider how many maps, textures, items, etc bein' created constantly by the users here, the game wouldn't be able to properly hold it all without collapsin'. Another thing to keep in mind. So even if, it'd be better that all the content not be put to public use but rather only a limited selection.
Then there's the obvious restraint that we cannot do much of anythin' without the source code which Kov hoards.