Deceptively complex QoL request.
Most classes make heavy use of the Fn keys, and many people rebind them to keys closer the WASD set. Problems arise when you try to play different classes; my Engineer and my Ranger rely heavily on F5 (as a Holo and a Druid respectively), Ele needs F1-4, Mesmer needs the same, Guard doesn't use above F3, Warrior doesn't even go above F2. Half the classes can weapon swap in combat, the others can't. If you wanna get really serious with a Mirage, you need to rebind your Elite skill, but no other class (apart from maybe the Bladesworn) wants to do that.
Other MMOs allow you to reposition skills around your action bars, but GW2 does not (e.g. both a tank DK and a Fury Warrior in WoW, I dragged my engage skill to 1, my main DPS ability on 2, conditional DPS ability on 3, interupt on 4, 5 and 6 for cleave skills, 0 for heal and - for stunbreak). I get why GW2 is different, specs are balanced around far tighter control (and the pay off is every skill can have a far higher power budget). But with this, each skill on a character becomes so much more important, especially mode switches like Necro Shroud or Photon Forge or the Bladesworns Gunsaber; and these are rarely on the same key.
So you can only optimise a keybind layout for one or two characters; I main my Holosmith Engi and occasionally take my Druid into endgame PvE, and the only reason I can do both is both have their critical mechanic on the same key (default F5, rebound to MB5). I cannot unify, say, the Default F1 modeswaps like Rev Legend swap, or Warrior Bursts/Gunsaber, because they correspond to Toolbelt-Heal for all Engineers, and Set Pet on Current Target for all Rangers. And now we have Bladeswon, with a double mode switch, from weapons to Gunsaber on F1, and then Gunsaber to Dragon Trigger on F2.
So can we please have a per character keybind over-ride list, so that we can play multiple characters to an enjoyable level, without having to break all our keybinds every time.