Things that make me go HMMMM... And why they are not in the game yet.

[Enkidoh]

3.) Duel Anywhere.
Just drop a nice fat PVP circle in a location, and if you run out it cancels the encounter, and you instead of death you are dropped to 1 HP, before receiving a nice HP regen shortly after. Cannot be activated when in combat, and have a button that either auto-declines a challenge or just grays out the option to other players. would be nice, then on top of that have Group vs Group PvP. Just for fun, would be nice, be nice for guild wars, etc.

Yoshi knows that such a system would only lead to massive griefing by high level players deliberately attacking newbies/low level players (accessability to players of all persuasions and ability level being a major selling point for the game) and so he wants to avoid this, and so is not interested in introducing open world duelling. The closest you will ever have to such a open world PvP duelling system is the Duel Circle at the Wolves's Den that was added back during Heavensward's patch cycle... and that is now barely used (I forget it even exists). So it's pretty telling that even most players do not care for such an idea.

Also FFXIV is fundamentally a PvE-centric MMORPG, with PvP a secondary aspect to the game. PvP is thus content seperate from the main game, and always will be. Free PvP duelling anywhere is counter to that, and thus will never happen I'm afraid.