Its possible, but no commitment yet. We've sort of looked at it from 2 different angles. On one hand we have some sort of reactive features already like with the Sovereign skin line, where when you get a kill, the gems on the back glow and give off some little particles. We can continue doing things like that that are subtle but help emphasis that moment of getting a kill for the player.
When it comes to things evolving or changing, we'd probably treat it similar, keep it subtle and work progressively toward a final version. A lot of times we see this in games it involves things like color changes, glowing, etc, and we'd need to find the appropriate end cap. Do we reset your advances on death? Do we let you keep those advances round to round? What if someone picks your gun up and starts killing with it?
Variables like this are all things to take into consideration so we want to make sure we've gone over all of our options before going all in on an idea, but rest assured the Premium Content team is always looking for ways like this to push the bar :)