It'd be interesting to have such a feature, but more interesting if it was used to unlock lore/bestiary kinds of information.
For example, play as a Morbol to to unlock a Bestiary on Morbols that you can read at your leisure.

At best though, it'd be a fun minigame that served no real purpose. And we all know that the most vocal parts of the playerbase would call it Dead on Arrival if it wasn't awarding the best ilvl gear in the game.