I much prefer to see some 'proper' French words dropped into the conversation rather than "ze", "iz" and "leetle" being used to symbolise the French accent - probably because my officemate was French and she used to drop French words into conversation. But saying that, please don't do what Kate Mosse did in Labyrinth when she used a French word and then had the next person translate it for the reader, e.g.

"I would like a chou-fleur."

"A cauliflower? Bien sur!"

"Of course, merci beaucoup."

"No - thank you."

I'm exaggerating only slightly.

And I have no problem with elves, but beware pointy ear prejudice!