Luke Smith, the Director of Destiny: The Taken King, shed some light on the game's Light value. Posting on NeoGAF, Smith said that the maximum Light value for content currently in the game—including challenges within the King's Fall raid—sits at 300, and there is no meaningful progression beyond that level, at least at the moment.
"The Forever 29 meme isn't an apt comparison at all. And everytime someone stretches to trying to make it, I shake my head," he said. "Raid final boss isn't 310 (so you aren't pushing against something you can't attain), and so there's no meaningful progression content above 300 for you right now so being 307 or 308 in week 2 doesn't really matter in terms of power (vertical) progression."
"The max Light value for content currently in the game is 300, once you've crossed that threshold, you can climb all of the mountains currently on your horizon."
Smith added that the inner workings of the game's investment and reward systems will remain a secret, but calling it "smart loot" isn't the best way to describe how it works.
"I will probably never detail investment and reward systems, but 'smart loot' isn't the right term (I think this is the first time I've even said it, and it shouldn't have ever been used because it sets a bunch of expectations in ways the game simply isn't going to meet) and it isn't a catch-all for every piece of gear that drops," he said.
"As for your anecdotal evidence re: Raid Drops. Yep, some people got lucky some people didn't. What I will say is, if you got a helmet in the first or second week, luck was truly on your side. Exotic Engrams don't have a lot they can roll from (e.g. Hunter chests), so you're going to naturally see more duplicates. Most of the new weapons are found through quests, not through Exotics or Three of Coin Engrams."
Smith says that he plans to look into the Ghost slot once he returns to Bungie's offices, which at the present is hard to get drops for and thus keeps players from raising their light levels to higher thresholds.
Given his comments, we can certainly expect Bungie to keep tweaking the game balance as they release more content and updates.