Why not a dynamic myth cap based on number of classes at 50?

[Nonlinear314]

(e.g. it wouldn't impact people's behavior).

Interesting point, but do you have any actual evidence that it would or wouldn't impact people's behavior?

And if people level another class to 50 just to get a marginal myth bonus for their main, maybe 50 more tomes? So what? They can already spend an extra week leveling a fresh alt to 50 and get twice as many tomes, a second raid lockout, a second piece of gear from CT each week.

My main point is that as it stands there is little incentive or benefit to leveling more than a few classes on any one character before making an alt and leveling other classes on it. It's just a waste of time. There needs to be because as it stands the armory is just a progression trap.