Fortunately, it's just vague enough, where it's subject to interpretation, so that both camps - those in favour of it and those against - could be satisfied. Personally, I would've loved for them to have had a gratuitous sex scene - but not in Gene Roddenberry's STAR TREK, thank you, very much! We weren't going to get that.
I thought the breakfast scene in Qpid was pretty clear, but yes, a gratuitous sex scene would have been too much for TV and for me.
That is what fanfiction is for. At least in most of my stories.
She would never be allowed to act as civilian archeologist on the Enteprise.
Why not? Vash is an archaeologist and acts much the way the other archaeologist shown in TNG act. According to canon, before meeting Picard on Risa she spent five years working as a personal assistant to Professor Samuel Estragon, an archaeologist who's work Picard knew. It was Professor Samuel Estragon who was originally hunting for the Tox Uthat. It was also Professor Samuel Estragon who hired the Ferengi Sovak to aid in his explorations, especially in situations that weren't quite ethical. Moreover, Picard isn't surprised at all and is amused by the idea. (3rd season episode Captain Holiday.)
Also in the 6th season episode "The Chase," Picard's own mentor Professor Galen comes aboard the Enterprise and attempts to BRIBE the captain with a Kurlan naiskos, very rare archaeological artifact, wanting Picard to leave his captaincy to become Galen's muscle.
GALEN
"... I'm sorry, Mister Picard. But that information has a price --your agreement to join me on the final leg of this expedition."
PICARD
"For how long?"
GALEN
"Three months. Perhaps a year. If we had a starship and complete diplomatic access -- a matter of weeks. But we'll have only my shuttle, the transports we can arrange, and our combined talents."
PICARD
"Why can't you do this without me?"
GALEN
"I'm not a young man. There will be hazards along the way. I don't want my own inadequacies to jeopardize the completion of this work."
In this episode Professor Galen is operating exactly the way we were told that Professor Samuel Estragon did and the way Vash did. Therefore, it is a believable extrapolation from series canon that fieldwork in interstellar archaeology can be a somewhat rough and tumble, wild wild west like business.
Besides, if Picard had wanted a 'good girl' for a perfect little wife he would have married Jenice Manheim. Instead, he ran from her. As O'Brien told Sisko, "The Captain likes a challenge." Vash is also a civilian which would negate that whole having to order his lover into dangerous situations problem.

Love this!
Warmest Wishes,
Whoa Nellie