I might be able to do things slightly differently for convenience. Maybe a drag and drop system. But I can't place a timeframe on such a thing at this time. I must stop adding things for awhile and fix up what is currently in the game; especially the code itself.
Regardless of what I change however, the one thing that will never change is the requirement of downloading the addons seperately. The point of the system is to remove myself from the equation. If i added them to the game directly like that, then any time an author wanted to change something, or if they wanted all of their content removed for any reason, I would have to do those changes myself, and they'd be limited to the monthly release cycle.
Removing myself means content updates can happen any day, instead of on my monthly schedule. Also, I don't have to do anything at all with the content, which if a lot of people start doing stuff, would eventually bury me. We're currently seeing about 2 new writers starting up per month.
Other than that requirement, we'll see what happens in the future.