Wouldn't it make more sense as a "normal" toggle so that it is either on/off?
In it's current "semi-toggle" state, sometimes Overload lasts for 5 minutes, while other times it runs out in a matter of seconds. It's unpredictable nature and my inability to tell when it's about to run out (I play on console, so we can't see percentages and either your ultimate appears full, or not) sometimes causes me to get caught with my pants down in the middle of combat - leading to very frustrating and disorienting combat situations.
Even if ZOS doesn't want to make Overload a "normal" toggle (for whatever reason), could we, at the very least, get some kind of indicator as to when this ability will run out? It looks foolish when my character goes from slinging lightning projectiles at an enemy from 15 meters away to swinging a sword wildly at the air because Overload ran out and I've been automatically switched to a Sword and Shield.
How is this "semi-toggle" mechanic fun for anyone? It's such a cool ultimate ability, but it's remarkably frustrating and inconsistent in it's current state.