This is how I wear my hair 3-5 days out of the week.
latley I have been wearing a slightly less curly version of this because I think it looks less matronly and my hair is short. I have been experiementing with rolls too but I havent worn my hair in rolls in public yet.

Idealy I would like my hair to look like Vivien Leigh's in the early to mid 30's.

You're well on your way to the goal. That's a lovely style.

I have slightly layered hair and don't usually curl it when I'm at work, I prefer my sleep in the morning It doesn't look very modern but I think that's because my hairdresser cuts it in a very 40s style so although it has layers it's a good cut.

I've had a bad experience with one hairdresser who didn't comprehend the words 'slight layers' and I ended up with a very modern hair cut. It took about 3 weeks for it to grow enough for me to get it cut again.

That's exactly what I'm worried about. I'm also afraid that if I get it layered, it will be too "fluffy", even if I don't curl it.

I have a very good stylist (she can't do an updo or set to save her life, but she's great and cutting and a modern blow dry).

If I want a good modern look this cut still works for me, especially if I blow dry (which I hate to do, I'd rather set it!).

But if you wash it the night before and smooth some kind of "product" on it (the kind used to keep frizz down) and let it air dry it should still be fine.

Look around at the people in your area. If you like the look of someone's haircut, speak up and ask her where she goes, and to whom.

The first time I had Claudia cut my hair I brought in an old hairdresser's manual and went over it with her. If you just hand one to most modern stylists they just say, "Oh, how cute!"...and set it aside.

Also, if this stylist is good you should ask him or her to taper the ends slightly. My hair is too blunt on the ends for a good modern look unless it's tapered. And tapering helps the ends curl under, anyway.

My hair has grown to Rita Hayworth length (when I'm lazy it's ponytail time).

But I've been putting it up (barely damp) on rag curlers; roll one section up, the next section in the opposite direction.

The look is ca. 1939; waves and fluffy curls, without much effort.

If I use product and a clip or two for water waves I can get more of a Rita Hayworth look.

I haven't tried for a mid-30s look at this length. It will probably require more curlers, product, and most of the front in water waves.

Has anyone tried for mid-30s with this hair length, either their own or in styling someone else's hair? How did it work out?

I cheat a little.

Get the long clips, curved if you can find them; they work better.

I make sure there's a little product and that the hair is uniformly damp and swirl it into the wave I want with a comb, then anchor the wave with 1 - 3 clips.

That's something you can't sleep on; you'll have to sit under a dryer for it to take.

Oh, make sure to section your hair horizontally as well as vertically for this to work. My hair is pretty thick (less so than yours, I think) and I usually wave the top half in two sections, leaving the bottom two to curl.