You're skirting close to ARR now- a lot of buffs (like the Heavy Thrust piercing debuff) were only granted if you hit the positional in 2.X.
Eventually, SE decided that was too punishing and moved away from it. I actually think what you're proposing if more punishing than what we have now- or just the same. A stacking crit buff is just damage with a different hat. The small potency gain is fine as a reward for hitting your positionals.
I, too, yearn for the days where XIV strips every mechanic away from its jobs. Just make them all a one-button, auto-rotation jobs so I can press 1 really hard with no thought or learning curve. (obvious /s)
This is working out so well for the game too, between the healer threads (and the scarcity of healers in a lot of DCs pfs since like two years ago), a lot of reworked/simplified jobs (like BLM and MNK) having abysmal play rates, and so on.
Let's not pretend that these weren't missteps by SE- they love to gut their jobs down to appease the lowest common denominator (which is low in this game), but that doesn't seem to be working too well if they're thinking that they need to revise their strategy (which has been publicly stated multiple times). Especially if the story content goes on the way 7.0 is going. No story and no good job design is sure to be a winning combination.
Fwiw, that's not why BRD/MCH cast bars were removed. The identity of those jobs was, in part, their mobility, which people enjoyed. Stormblood BRD, in particular, was a very busy, high-apm job during it's lengthy burst phase (especially with the dot tick crits procing your bloodletter, you had to be spamming that thing constantly) with a lot of small intricacies to maximize it. I very much doubt it was about "making it easier to maximize damage" since they literally shifted the difficulty from one thing to another; HW and SB BRD were very much comparable in execution (also true for MCH, but BRD was the harder of the two jobs for both expansions).