Dissipation has for a very long time been considered a weak skill in SCH's arsenal due to its lack of synergie with the rest of its toolkit.
Due to this it is usually only used during the opener for an extra dps.
Additionaly, Dissipation tends to confuse new players due to its effect. Any casual Scholar will consider this to be an emergency heal tool. However this is, most of the time, far from reality because the healing bonus effect does not apply to SCH abilties, which is at odd with it granting 3 AF stacks. That on top of the fairy being gone for a whooping 30s makes it really uninteresting in most situation beside a powerful deployement as not only do you loose the heal of the fairy (but that's the point of the 20% heal bonus) but more specifically, the gauge doesn't fill from using AF as she's gone which again is at odd with the skill as a whole.
[Important change that NEED to be done]
Change the healing effect to also affect abilities.
In otherwords "Increase healing action potency by 20%"
This would make the skill more coherent with the rest of SCH kit.
It is incredibly weird that a skill which grant 3 AF and a healing buff doesn't affect the related skills.
[QoL changes that would make the skill less frustrating]
Allow the Fairy gauge to still be filled while the fairy is gone during Dissipation.
As Dissipation is a buff, it should be possible to add a new effect such as
"Using Lustrate, Sacred Soil, Indomability or Excogitation or Energy Drain also increase fairy gauge by 10"
[Change that would be nice but would affect balance a little bit]
Reduce the duration to 15s.
30s is simply too long for its intended purpose (spare a few niche moment)
It'd see much more use if the duration was reduced.
[Change that would be nice and make the skill much stronger]
Add a new effect "Your next Indomability or Excogitation can be used regardless of their state once"
As in, even if they're on CD you can still use one of them once.
The issue with Dissipation current design is that, assuming you do want it for healing and more especially AF usage (which assumes we'll need to actually heal more), you'll more than likely have most of your ogcd on CD by that time.
Allowing the use of a single Indom or Excogitation to be used once every 180s wouldn't break the game and make the skill feel more complete and add some weight to it beyond "3 energy drain" or "super deploy for the lolz"