While its true that most engagements in the show take place at ranges measured in paces rather than the close quarters of Fight!, I think the feel of Fight! does accurately capture the tension of these conflicts. Consider Zuko and Azula’s Agni Kai. The two are never even within polearm striking distance, yet it is clearly better described by Fight! than Range and Cover. That said, Range and Cover describes some other conflicts well. The invasion of the Fire Nation on the Day of Black Sun, for example, or the numerous scenes where Team Avatar is fleeing on Appa’s back from firebenders.
Part of my intention with the draw mechanic is to abstract the process of using specific bending forms (water whip vs water octopus vs wave, for example). The players have the freedom to describe how they’re attacking their opponent, and the Draw action allows them to turn this into mechanical advantages. While it is not on my above post, I’m also going to allow Draw successes to be spent on adding additional targets and increasing weapon length. Though I haven’t considered Range and Cover yet (mostly because I’m far less familiar with it), I imagine I’ll have a similar mechanic to increase weapon range. I’m also extending the Draw action to Firebenders and Airbenders, though it is less useful for them and never mandatory.
To consider one of your examples, Firebending is by default a closer range, quick striking style. A firebender may spend successes to increase the range of their attacks. Whether this is via a projectile fireball or a long fire stream is up to them. Likewise, if they spend successes to increase the number of targets, they choose whether they do this via breathing fire or shooting fire out of both hands at once.
In summary, I agree that bending is a “grab bag” of weapons, but I think that this should represented with an abstract, fluid system rather than creating a Weapons Table for each bending style.