Less suggestion more complaint first. It would be nice to be able to change names to one that hasn't been active in years. I do understand the terrible side of this.
Actually suggestion would be allowing players to switch their displayed names in game rather than their actual account names, a lot like skin changes. Maybe this can be done and I just don't know it.
I agree on the "If this account hadn't been active in years, let us have the name". I don't think there is any way of knowing if a certain account had been active for years.
I don't think changing your name in game would work. For reasons of servers. (And if someone else has the name).
But I don't know these things, so don't quote me on that.