SE should steal a page from LOTRO when it comes to job design. There was a job in LOTRO, Warden, that I'd swear is where SE got the idea for NIN mudras.

Warden had 4 abilities plus the "execute" ability. These abilities could be used in various permutations along with "execute" for AOE damage, single target damage, AOE DoT, single target DoT, self buff damage/mitigation/regen/group-regen, debuff enemy defense/attack/speed

You could use 2, 3 or 4 of these abilities to create various combinations. If I recall, you could even double up on the ability. I think the job had something like 30 or so combinations last time I played (almost a decade ago).

Of course, in the FFXIV universe, we can't have a job be able to buff/debuff/self-heal/group-heal/DPS proficiently due to the tank/heal/dps role restrictions. The LOTRO warden was mostly defined as a tank, so the "burst DPS" was a bit muted to offset how OP the job was.

I mainly bring this up because the job did not have button bloat (minimal buttons) but high job complexity.