are there any skills/technics that are pretty much obsolete/worthless?

[nomi]

i made a newman and decided that i'll try to level skills up on my cast because it would be easier as a 75 cast than a level 8 newman but i wasn't aware there was a limit on how many PA you can have so it makes me ask if there are certain ones that are more important than the others

as a gunner it was easy since its just single elements for weapon types and i only use rifles and shotguns (and dark machinegun) but technics there are like 5 different spells for every element and i would like some practical feedback on their usefulness. atm my favorite is the earth projectile booger attack and every elementals "blast" technic, least favorite are the "breath" technics.

i'm mainly talking about attack ones and not support/debuff.

[Dragwind]

You can turn your Photon Arts back into discs and they will retain their level. You can then swap them out for others at any time and re-learn them when you feel like it, so keep that in mind.

As far as attack technics that pretty much suck, Megiverse and Nosmegid always come to mind for me, though those two are arguable.