Skills should scale down in lower content NOT be greyed out.

[Packetdancer]

Okay, so, I could sit here and numerically prove why this is not a simple problem to solve. (Because math!) However, I've done that in these threads before, and my experience is that people's eyes tend to glaze over when I do. (Because math!)

I swear to the Twelve, I will start to Math at you all if I have to in order to prove why this is not a simple problem to solve without significantly reworking FFXIV's combat system (to the point it will no longer be FFXIV's combat system). And if I do so, it will be in typical Packetdancer manner: in sufficient depth that I will need to break it into multiple posts or else link a Google Doc.

Consider that a promise and/or threat as suits your personal preferences. :P

[Rein_eon_Osborne]

I swear to the Twelve, I will start to Math at you all if I have to in order to prove why this is not a simple problem to solve without significantly reworking FFXIV's combat system (to the point it will no longer be FFXIV's combat system). And if I do so, it will be in typical Packetdancer manner: in sufficient depth that I will need to break it into multiple posts or else link a Google Doc.

Consider that a promise and/or threat as suits your personal preferences. :P

A threat or not, I am very interested to snack on your google doc link and its content.

Grace us with thy math!

So you would want to do more skill for the same amout of damage you would do for just 2 moves.

Ngl, the next thing that will surfaces is "Omg this is unfair why do I need to work 2-5 times harder just to achieve same damage, I'm not gonna do stuff on low lv dungeons anymore!"

[Mikey_R]

A threat or not, I am very interested to snack on your google doc link and its content.

Grace us with thy math!

You can do some very basic maths yourself if you feel inclined. I would suggest doing AoE attacks as they is the simpler one to look at. Take Paladin:

Level 15, Total Eclipse, 100 potency per GCD (P/G)
Level 40, Prominence, 170 potency, combos off of TE for 135 P/G

Now, this is where it gets fun:
Level 72, Magic Circle, 300 potency under Requiescat (which you will always do), 300 P/G for 5 GCDs, more than twice as much as the physical combo
Level 80, Confiteor, 900 potency, this alone increases the magic phase to 420 P/G, but wait, there is more
Level 90, Blade combo, 250 > 350 > 420 + 560 DoT = 526.6 P/G for those 3 attacks alone (half for anything not the main target)

For a level 90 PLD in an AoE situation I will use the following string of attacks:
TE > Prom > MCx4 > Con > Blade which is 10 attacks total At lower levels, replace with TE > Prom where applicable

Level 15 (all TE) 100 P/G
Level 40 (TE > Prom x5) 135 P/G
Level 72 (TE > Prom > MCx5 > TEx2+Prom) 214 P/G
Level 80 (TE > Prom > MCx4 > Con > TEx2 + Prom) 274 P/G
Level 90 (As detailed above) 405 P/G on main enemy 316 P/G on the remaining (only part where there is damage falloff)

Of course, this doesn't take into account CoS (225 DoT on everything) or the fact Spirits Within goes from 250 ST to 300 AoE with 50% falloff, however the main takeaway is, there isn't going to be a universal multiplier, or a magic formula you can use for everything, so it would all have to be done individually, for each dungeon for every job. Remember as well, AoE combos are easy, it's the single target where things get even more complex.