Welcome to my perfumed garden

"except that in historical AUs, modern-day slang tends to seriously *detract* from the zeitgeist of the piece."
Afraid I don't agree with you there. Do we always look for era-appropriate slang then, which to my mind has that 'Tony Curtis' sound? We're not actually writing the piece in 2ndCBC Latin and Greek so all of the language is an interpretation from what the characters would have been saying. When Blair says 'man' and whatever - he's really speaking Latin and Greek so I'm interpreting his slang (as I was taught to do by some excellent classics scholars) to make the ancient characters speak to us as they spoke to their contemporaries and not sound dry and ancient and impenetrable.

I wouldn't include stories within literary English history (although writing them in historically correct English still makes them sound unusual and they *wouldn't* have to each other - it depends on whether the characters are speaking to us, as they do in Mab's stories for example, in which case they are perfectly correct to speak the syntax of their time - or each other, in which case they should be interpreted for modern idiom.) - Characters speaking to each other in cod ancient tongues sounds 'historicalese' to my ears and tendeth to make me giggle. I'm sorry if the way I wrote A&O didn't work for you but I wouldn't have written it any other way.

"if not, there are modes of speaking that will convey level of formality just fine without resorting to modern slang."
I didn't resort to modern slang, I chose it quite deliberately.

"but also, what tends to irk me about historical AUs is that a lot of them ring false on the set-up. "
I hope you're talking in general - no story could have been more rigorously researched than A&O. My collaborator, Ali, is a professional Romanist at a very good university; I studied the classics extensively. There was practically nothing in the story that was in any way historically inaccurate - including the level of informality and relationship between the characters (Blair wasn't a slave but a scholar but there are plenty of contemporary accounts that demonstrate very close, informal relations between master and slave).

"various societies had very strict rules about not consorting with outsiders. the jews were one of these societies."
Not unobservant Jews and they were many. Neither Blair nor Naomi were in any way religious Jews - Blair actually states this in the story. Jews were everywhere in the ancient world - anyone who towed the line was acceptable to Rome.

As for the names, they're always a problem. We changed Jim, William and Simon but never could hit on a suitable replacement for Blair (which is Scots; a pretty common surname around these parts, actually). Blair says it's a nickname (states its meaning) and actually lists all the names by which he's been known in all the languages they've encountered as they travelled - OK it's a fudge, but a pretty minor one I think.

I get the strong impression you didn't like A&O, which is shame but no one's going to like everything I write. - The story was written *exactly* as I meant it to be written. It was as historically/societally accurately as we could manage in the context of a fanfic; twisting an already fictional story about fictional creatures, the Sentinels. It was written in language that was deliberately modern for the reasons I've already mentioned - and, I'm sorry you didn't enjoy it.