Not that I've seen, so you're pretty much going to have to use trial and error.

Personally, I'd say use a scale of 1 to 5, with 1 being "minor bumps and bruises" and 5 being "serious risk to life and limb," and the rating you give to the degree of physical harm that could result is how many Wounds can result from the Risk, though I would suggest erring a bit on the cinematic side.  Risks that can deal 2 or 3 Wounds should probably the be norm, so that the PCs have a decent chance to avoid serious harm while sitll succeeding; save the really dangerous Risks for dramatic moments.

As an example, if you watch the various Indiana Jones movies, most of the Risks that Indy finds himself dealing with would probably have a result of 3 Wounds if failed.  But he's Indy, so he's generally good enough to be able to succeed, activate an opportunity or two along the way, and only take a single Wound at most.  Of course, his luck being what it is he sometimes doesn't roll so hot and barely scrapes together a couple of raises, meaning that in some Risks he takes a bit more of a beating while still able to succeed and activating an opportunity.

The risk does not have to be damage. It can be other problems. A consequence can be a guard looking in their direction as they sneak in. It can be "the item they want rolls off the ship into the water" or "the Bishop recognizes you from last night's robbery". You can make the consequence an individual or group cost. I did a few fory last adventure where the group had to spend 3 raises total among the 5 players.

For new characters 2 seems a good threat. While they could take more damage, the odds are that they will not have enough raises to pay that off, effect the scene in a significant way AND take up any opportunities. You want them debating the best use of their raises but you don't want them needing all their raises to avoid the consequences.

I actually wasn't thinking about that consequence in a sneaking risk because in my games lately, the sneaking has not been the priority. And you are right that it should not negate a successful risk. The problem with a table is that the idea im this system is to tailor everything to the scene and players. What is a challenge for your table of 3 beginners may not be for 3 beginners that took different backgrounds. (3 players with 4 finesse and 4 hide will have more raises to sneak in that 3 players with 2 finesse and 0 hide). And both groups will struggle where a group of 10 players can spread the costs out on the shared factors and then easily afford personal consequences.

I don't have play experience yet, so take any of the following with a grain of salt.

I'd suggest basing this on the Hero's capabilities. Since you know that (on average) a Hero will get about half the dice rolled in Raises, you can plan Consequences around this average. I would first leave room for the Raise to succeed and any purely-narrative Consequences (these are more interesting from a story perspective, and I'd favor them where possible).

For example, assuming a player will roll ten dice (five Raises on average):

• Assume they'll use one Raise to succeed at the Risk (four left)
• Set a plot-complicating Consequence (three left)
• Set a Consequence that could be a setback for the Hero later on (two left)
• Assign a Wound Consequence equal to the remaining Raises or just slightly higher - so, a Consequence of 2-4 Wounds in this case (no Raises left on an average result)
• Set any Opportunities that sound fitting - I'd suggest deciding on these after the average number of Raises are accounted for, so the player would have to decide between getting this at a cost unless they rolled exceptionally well.

Ideally, I think it would be best for about one or two Consequences / Wounds to result from a Risk on average. If the players succeed without cost throughout a session, I could see them loosing interesting in the resolution mechanics. The opposite problem would happen if they can't cancel most of the Consequences they're facing. So, depending on how the players performed, I'd swing this estimate up or down appropriately as the session progressed. Ideally, you should have an upward trend as things get more dangerous, although a night that starts with catastrophic failure and gradually works around to a win for the Heroes is interesting, as well.

Alternatively, if you prefer more fixed Wound Consequences, I'd base them on the assumption that a typical "bad injury" from a fight would be roughly equivalent to a Slash from a duelist (3 to 5 Wounds for a Hero). Typical situational damage (fire, smaller falling debris, falling from a moderate height) should probably hazard somewhere in the neighborhood of 3-5 Wounds. Any thing potentially threatening life and limb (an explosion, deadly falling object like large stones, falling from a high precipe) would probably be twice as dangerous, around 6-10 Wounds. Anything that would be instant death for a non-Hero (being inside a collapsing exploding stone fort as it slides off a cliff) could probably be set to four times this ammount or more (16-20 sounds reasonable for this, the Hero can't die, after all, but they'll be in a bad way).

 

16-20 will be too high in most cases. You have to keep in mind when planning that the players will be taking little wounds from combat, earlier consequences and other incidents. And they need to be on their feet for your final conflict scene with a shot at winning. You CAN leave the amount blank on your plot and decide at the time as well, nobody would know but you.

Here is what I'm cooking up for my "GM Screen".  It hasn't really been tested, so some of this may be low-balled a bit.  I'm working from the baseline that 5 wounds = a critical wound.  So the more dangerous you want a situation to be, the more critcal wounds you need to dangle in front of the heroes.

Wounds as Consequences

Risky: 2-3 Wounds per Hero

Dangerous: 3-5 Wounds per Hero

Perilous: 6-9 Wounds per Hero

Deadly: 10+ Wounds per Hero

Accurate but outside of a few situational issues and some help from blessings, most characters will never roll more than 13 dice which means 7 raises. Assuming the complete the risk with a raise, their best effort against 10 wounds still nets them 4 damage. My thoughts still hold that consequence should be totally negateable if the player chooses to do so and ignores everything but the risk. (And 13 dice assumes rank 5 trait, skill, flair, description, and an extra advantage die). Mind I did not factor exploding dice.

@BluSpong, thanks for that table. I notice that 7th Sea 2e core rules make use of improvisation a lot, but that requires experienced GMs. To tables are useful, even if a caveat is reiterated about "rulings not rules" so that all rules are just guidance but not set in stone.