Denko and Nalbandian are well known for their return.
Melzer, Nishikori and especially Cilic are good choices though. One tends to forget how great a returner Cilic is because of his general muginess.
Yup, Cilic is the best returner of serve I've seen at that height. Of course he's also arguably the worst server among giants and mentally... well let's not even go there, but his return is often overlooked.
Nishikori is a great returner, but too often he is too ambitious on 1st serves returns instead of just getting them back in play, which sometimes hurts him I feel. Melzer also an underrated returner, probably the best returner of serve among 'mugs' ie players outside the top 20.