So before I go into the section by section, I would believe that we have reached agreements on Pyryem, Porte, and El Fuego Adentro at the very least, correct?
Looks like we're pretty much on the same page for Pyeryem and Fuego.
Porte: -3 for the ability, which grants the ability to pull a set number of items out of nowhere (the "Bring" knack), create a pocket to store things (the "Pocket" knack), a viable reason to "block" some attacks (the "Catch" knack), the ability to detect some objects (the "Attunement" knack) and emulate a limited version of Worldwalker (the "walk" knack, with the ability to make some maneuvers in the process). Or do you think it should be more expensive when you take all of the knacks into consideration?
I'd part it out, actually, so that someone could take the knacks they wanted and leave the others for later. Bring is the baseline, and I'd call it -1. I don't recall the exact mechanics on Pocket or Attunement, but expanding the ability to store objects (but not people) probably only reaches a -1, and the ability to know where your objects of interest is should really be folded into the base power. Catch is probably no more powerful than the Footwork stunt, though mechanical representation is an interesting question, so that's again a -1. And the actual Walking, I'd set at a base -2 for the ability to move yourself, with another -1 when you can carry people with you. It's much faster and more secure than Nevernever travel, but it also has far fewer possible destinations.
Honestly, I can see a good Sorte "block" as twisting the strands to keep someone from coming at them. Don't want to fight this person? Fray the sword strand; they have to overcome the Block to get to you. Fray a cups strand, and they won't be able to speak against you in social combat without overcoming it.
I see Sorte as being more subtle than most Blocks, working with existing circumstances and conditions to make action easier or more difficult, rather than creating an entirely new barrier or threat. That's why my inclination is to treat it as maneuvers, creating and tagging aspects to manipulate the situation.
So...yeah. While Breath Weapon/Natural Weapon shows the damage side and how said damage can apply to creating aspects, it doesn't really show that it CAN be more advanced when you think about it. I can see it being used to defend by dissolving ranged weapons (melee will take some thought), create a block via a dissolving field (or even just bad footing), and as previously mentioned, make attacks or create (or destroy) scene aspects.
That being said, I do agree that they shouldn't have the counter-magic side of things, but since you wouldn't be using most normal magic rules in 7th Sea, this becomes a moot point, as I think the only counter-magic is the Thomas knack from Glamour.
Just my two cents, anyway.
I'm not going to call it badwrongfun to treat Zerstorung as having the flexibility of Channeling; it's just not how I'd do it. I'd recommend not going to full Sponsored Magic, though, since A) Zerstorung rituals aren't a thing I recall existing by book and B) if they did, they'd mostly be death curses, which are bad mojo from a gamist standpoint. Evil wizards who can dissolve you are scary enough if they have to be in the room with you.
I think this one might be a personal preference. I just recall having a player carve a Villskap rune and striking down an entire Brute Squad with a lightning bolt to escape from a jail cell. Good times. . .
Honestly, I wouldn't take that one away since at the beginning, runes are temporary (you have to hit Adept to have a permanent rune on something, then Master to become said rune), but that's my preference/approach to things.
Again, tastes differ; if your table enjoys runic evocation, rather than a limited number of uses a la open potion slots, that doesn't hurt my game any.
This...actually makes perfect sense. So you aren't acting in accordance to the AGENDA of the Legend, but rather acting in accordance to the PERSONALITY of that Legend. Added bonus (or alternative if the situation warrants) if the situation and deeds are tied to Avalon/The Sidhe?
Probably a compel (or self-compel for extra fate points) on the Glamour mage's high concept; the particular legend might not be in favor of a united Avalon or the Sidhe's current agenda, but that doesn't mean that the mage's faerie blood doesn't have its own strings to pull.
Oh, it is compel-fodder. Perhaps if someone is unlicensed, they would have to tie it to the Swordsman School Aspect ("Illegal Donovan Duelist" or "Secretly Trained Valroux," for example)?
I agree with the reputation as a stunt, and perhaps even using a stunt to allow the Weapons skill to replace Contacts/Resources at the cost of a FP (to denote people you know or "resources" at hand due to your standing in the Guild)?
For a stunt, I'd say "Use Weapons instead of Contacts whenever dealing with members of the Swordsman's Guild". No Fate point charge, but limited usage; it'll get you mercenaries, and information at a very narrow level, which is about one trapping's worth.
On a further swordsman school note, which swordsman knacks and special abilities do you think would warrant special stunts? I figured a good number of the schools would use anything related to two weapons, but the other stunts in DFRPG aren't really going to cover things like Double Parry, the Bind-Disarm, etc.
The one that springs to mind immediately is Corps-a-Corps. Many of the others don't
need stunts but could benefit from them; e.g. anyone can use Weapons to create an aspect of Missing his Hat, but with the Tagging stunt, those aspects are worth +3 when first invoked if it's for a social attack rather than a physical one. But Corps-a-Corps seems like it could use its own rules; maybe using Weapons to initiate a Grapple?