For me, the guild is the government of Malifaux. So its bureaucratic. A department for every situation... You got a problem with undead, go to line 3 and speak with the death marshals. You got a problem with an arcanist, proceed to line 2 and speak with the department of witches. Got a problem with the locals (neverborn) we'll put the family on it. Got a problem with a automatons, go talk to C. Hoffman, you'll find him in the dept of automaton research.
The play style of the guild is that they are every play style or more to the point keeping all other play styles in check.
In game terms they have access to alot of scheme marker manipulation. (more than other factions or at least it seems that way)
They do have the best spellcaster in the game with Sonia's ability to be Ca 9.
Lady J is pretty straight forward in her style, she's really really really good at putting out alot of damage but pretty much only in melee. It can make her seem rather one dimensional. To get the best out of her (to take advantage of what she looses to be one of the highest melee damage producers in the game) she needs to be in combat and that limits her in other areas of the game possibly more so than any other master currently released. She has more synergy with her crew than in 1.5 but its still not alot of synergy. She does her thing, and her henchman the judge handles the minions she brings along.