How to make tanks more fun to play (devs please read)

[Pooky_Pasha]

Thirdly, to those who are accusing me of being a bad player / not educated tank by spamming uncomboed Halone;

Well, the thing is you really are playing poorly/not educated. Lets look at the abilities:
Fast Blade: Delivers and attack with a potency of 150 (threat modifier 1.5)
Savage Blade: Delivers an attack with a potency of 100. (threat modifier 4.5)

Additional Effect: Increased enmity
Combo Action: Fast Blade
Combo Potency: 200

Rage of Halone: Delivers an attack with a potency of 100 (threat modifier 7.5)

Additional Effect: Increased enmity
Combo Action: Savage Blade
Combo Potency: 260
Combo Bonus: Reduces target's strength by 10%
Duration: 20s

So 3xRage of Halone=3x100x7.5=2250 enmity since an un-comboed Halone is only 100 potency. (This would really be 1800 in Shield Oath due to 20% damage reduction)

Now for the Fast Blade >> Savage Blade >> Halone combo: 150x1.5 + 200x4.5 (since Savage Blade has a combo potency of 200 instead of 100) + 260x7.5 (since Halone has a combo potency of 260 instead of 100)=3075 enmity. (This would be 2460 in Shield Oath).

Taking (3075-2250)/2250x100~37% more enmity from a comboed Halone than a spammed Halone. Also, you're missing out on the Combo Bonus: Reduces target's strength by 10% by just spamming un-comboed Halones, and your overall damage will be roughly 50% lower than it should be, depending on how you use your off-gcd abilities. The same is also true of WAR Butcher Block spam vs Butcher Block combo.

It should also be noted that the data you linked is old, and I do not believe it reflects the enmity buff both tank jobs received from the 2.1 patch. Please don't quote me on that though, but it wouldn't change that comboed Halone is roughly 37% more effective than spammed Halone.

As for how to make PLD a little less boring, I've been thinking put Spirits Within as the tail end of the Fast Blade >> Riot Blade combo. It would something like:
Spirits Within: Delivers an attack with a potency of 200.
Combo Action: Riot Blade
Combo Bonus: Damage scales up with current HP (up to a potency of 300)
Non-combo Additional Effect: Silence Duration: 1 sec
That might bloat the ability, however. There would probably also need to be a 30 sec cool down on the Silence effect. I will let the theorycrafters pick that apart if they want.

tl:dr You're "mathematical facts" are wrong. Read tooltips and the entirety of the Valk chart you linked.