Would this compromise for positionals work?

[Shurrikhan]

Because positionals are not "fun".

All rotation that does not contribute to meaningful decisions is "busy work". That therefore comprises at least of 90% of all actions you will take and buttons you will press in this game. However, positionals not only take no additional keys for their added apm, but in the contexts of movement-requiring mechanics or limited space, do in fact add meaningful decisions.

Compare that against DRG's never-altered from 7-button melee combo, for instance, which provides zero decision-making and takes up 7, up from 0, additional keys for what amounts to automatic damage. (There's a reason button-consolidation mods can play DRG optimally off a single button each for ST and AoE GCD skills, but have literally nothing to offer for the likes of Monk beyond Perfect Balance -> Blitz.)

As XIV ARR was heavily based on early 2000s World of Warcraft, as per the development team's own admission, and they borrowed this mechanic.

Wow, that is some hardcore misinformation.

WoW has one positional, in the whole game: Backstab, which turns into Ambush under Stealth. That's it. That's probably the least positionals or positional elements of virtually any major MMO. ARR's positionals come primarily from the Yoshida period of XIV 1.x, when Yoshida added them in at no basis with or from WoW, and attached even frontal positionals to melee and rear positionals to tanks with a majority of weaponskills having positionals. Positionals are very much an XIV thing.

I'd gladly sacrifice them for more hectic encounters and interesting mechanics.

Positionals aren't taking away your mechanics. They're damn near irrelevant to performance compared to the simple likes of getting one more cycle of burst CDs out before the fight ends or downtime hitting at or just after the 2-minute mark, which encounter design already clearly doesn't give a damn about.

Positionals, are, however, often the only thing that makes our DDR/dodge mechanics constitute actual decision-making for those without cast times.