idk Dhark the same can really be true for any element (especially with comic book logic), but in the end sound is still only 1 type of element unlike most the other higher cost elements, like say weather, or magnetism.
I agree somewhat with Dhark. That force blast alone... Also sound the way Banshee has been seen to use it involves some elements of telepathy in particular hypnotism. Not to mention things such as voice mimicry and auditory illusions....
Well, weather mastery gets a ton of "elements" any many effects like AoE, 2x damage and stun, but it doesn't cost extra levels (I would however set the cost higher). So when it is a single, simple element that isn't that broad, I don't see a reason for the +x to Cost Level. Because if that is the case, then Water mastery is also rather powerful since living beings have water in them and you could then control them.
And if Banshee used it as telepathy, I am pretty sure he has Telepathy, just with a discount since it is tied into his "theme" power and a rename. They where also probably merged into the same action (don't remember if there was a in-game term for merging actions into one).
Even the boneheads at TSR and WotC recognized that sound/sonic is not a "simple" element-- the physics (actual physics even, not counting comic physics) of what can be done via the manipulation of sound waves is WELL beyond what can be done with most elements. I imagine Banshee's hypnotics/telepathy was more based on harmonic manipulations than overt telepathic action.
Sound Mastery is RARELY ever going to be discreet though, something to keep in mind. And much tougher to exclude area effect and collateral damages/efftects. Subsonics/Ultrasonics would expand or preclude a lot of the powers mileage though I'd personally make that a kicker or a cost in red stones to exercise
I do agree Weather should definitely get a cost kicker on one hand, ALTHOUGH what most people fail to account for with weather manipulation is the area/size and duration bits that SHOULD be factored in very heavily. YMMV.
End of the day, does it matter much though? The GM knows their players and will account for their creativity accordingly via cost kickers or appropriate challenges.
The things you are given from a MoE force blast are free which is why the entry says get a force blast with the appropriate effect. Otherwise all the other MoE characters with force blast would be paying the extra for theirs as well.