I'm not that much of an Asaro fan--the only one I felt was outstanding was The Last Hawk, which many of her real fans dislike. I think my main problem with her stuff is the way the books skip around in her universe's timeline, sometimes overlapping, sometimes with huge gaps--that, plus she's just got a writing style that I find needs some concentration. And lots of the time, I don't want to put that level of effort into my recreational reading. I do keep trying, however--there are a couple of her books on top of the dresser right now, waiting for me to get back to them.

If you'd like to give her a try, start with Primary Inversion, the first one she wrote. It's more a straightforward SF adventure, but with hints of the complexity that will come. If you like it, keep going!

For Burnett, I didn't know about her adult stuff either, until joining this Yahoo group that is a spinoff of the LordPeter/piffle groups. She was apparently a quite prolific writer of romances in the late 1800's-early 1900's. If you're interested, some of her books are now available as e-texts, as they are out of copyright. Try looking at The Online Books Page. Or you can usually find pretty cheap editions on ABEBooks--lots of them from British booksellers, as I recall. The one I liked better than Marchioness was T. Tembarom.