It probably won't help very much to simply name the other big names (you surely know about Heinlein and Clarke), but I was surprised to find Theodore Sturgeon's

It probably won't help very much to simply name the other big names (you surely know about Heinlein and Clarke), but I was surprised to find Theodore Sturgeon's stories to be quite intriguing, even though he seems not as well-known as aforementioned contemporaries. Try some of his short stories to get a feel for his oeuvre.