The way Xbox One players earn and show off their achievements (and Achievements) could change soon with the rumored addition of a new "Career" feature. According to a report from Windows Central (opens in new tab), there are documents and features which refer to this new system, including levels, prestige ranks, and loot crates for the upcoming Avatar revamp (opens in new tab).
So, what is Career? First off, it's nothing announced or official, so treat anything in this article with a healthy dose of skepticism. It could simply be a test run, or it could evolve into something else by the time it's unveiled. For now, it appears to be a new system that would exist alongside Gamerscore as a way of representing time and effort players sunk into their games.
Xbox platform chief Mike Ybarra told Windows Central in an August 2017 interview that Microsoft was looking into ways it could extend its recognition of player dedication beyond a simple number. "We are working towards a bigger, more meaningful change about somebody's gaming accomplishments in history, as a gamer on Xbox. We can do a lot more to reflect and let people show their gaming history and their status," Ybarra said (opens in new tab). "Somebody who only plays multiplayer in Halo 5 at a professional level, maybe they only have 2,000 Gamerscore, you want to be able to celebrate that person."
This Career mode would seem to be what Ybarra was alluding to, as it includes multiple ways to "level up" your profile, which would earn you loot boxes containing cosmetic flair for you and your Avatar. It should be noted that per Windows Central's report, said loot boxes do not appear to be purchasable with real world money.
The new Avatar system is expected to drop sometime in early 2018 - perhaps we'll hear more about this Career system then?