As an aspiring writer I read books I can learn from. When it comes to improving my prose my top picks are Jack Vance, Guy Gavriel Kay, and GRRM.
Of course, I'd probably mention others if I'd read them!
I would add that it's often a case of writers not being better or worse, just different. For example:
Whatever you say about A Dance with Dragons, I think GRRM upped his game in terms of writing quality. His prose brings detail and expansiveness and often (good use of short sentences) impact. I see his prose as somehow firm, rational, hammered out to near perfection, with hardly a comma out of place.
Gay Gavriel Kay's books have a more flowing, less studied prose. There certainly are commas out of place, but with that kind of rhythm and flow, who cares?
Coragem.