Love the OP and your username.
My favorite house is Lanvin. YSL is second, although Hedi Slimane has brought the brand down a bit with the name change and clothing.

Third would probably be Proenza Schouler though it's a shame they don't make menswear (yet).
I also don't really like traditional American brands because they're generally boring.
And my essentials are Lanvin sneakers, Prada or Ferragamo dress shoes/leather accessories, Hermčs jewelry, Burberry outerwear and YSL clothing. If I need something quick and cheap, I shop at Zara for the basics because they offer unique (aka stolen off the latest season's runway) designs.