José Rodrigo dos Santos in the same list as Eça de Queirós is offensive. Rodrigo dos Santos is the Portuguese-version of Dan Brown, not a literary giant.

To each its own. That is my list.

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Eça, is in my opinion, wrote the best novel available in the Portuguese language, "The Maias". I am not sure how good the English translation is, but he Portuguese original is sublime, especially if you are familiar with Portuguese society. Many of the peculiarities he wrote about are still recognizable 100 years later.

To your wife's excellent list I would add Fernando Pessoa a prolific genius and also Jose Regio, who wrote, Cantigo Negro, my favorite Portuguese poem:

"come this way" — some say with sweet eyes opening their arms, and certain that it would be good if I would listen when they say: "come this way"! I look at them with languidly, (my eyes filled with irony and tiredness) and I cross my arms, and I never go that way... this is my glory: to create inhumanity! to accompany no one. — for I live with the same unwillingness with which i tore my mother's womb no, I won't go that way! I only go where my own steps take me... if to what I seek to know no one can answer why do you repeat: "come this way"?

I rather crawl thru muddy alleys, to whirl in the wind, like rags, to drag my bleeding feet, than to go that way... if I came to this world, it was only to deflower virgin forests, and to draw my own footsteps in the unexplored sand! all else I do is worth nothing.

how can you be the ones that give me impulses, tools and courage to overcome my own obstacles? the blood of our ancestors runs thru your veins, And you love what is easy! I love the Far and the Mirage, I loves the abysses, the torrents, the deserts...

go! you have roads, you have gardens, you have flower-beds, you have a nation, you have roofs, and you have rules, and treaties, and philosophers, and wise men. I have my Madness! I hold it high like a torch burning in the dark night, and I feel foam, and blood, and chants on my lips... God and the Devil guide me, no one else! everyone's had a father, everyone's had a mother; but I, who never begin or end, was born of the love between God and the Devil.

ah! don't give me sympathetic intentions! don't asks me for definitions! don't tells me: "come this way"! my life is a whirlwind that broke loose, it's a wave that rose. it's one more atom that ignited... I don’t know which way I’ll go, I don't know where I'm going to, - I know I'm not going that way!

+1 for Eça de Queiroz. With the exception of O Crime do Padre Amaro which can in places be a bit blunt, he tends to have a a kind admiration for his characters as he quietly makes fun of them and the decadent society around them.

What I love about his stories is that they could be easily applied to modern Portuguese society, and would be for the most part still up to date.

That unfortunately leads us to other philosophical questions, though.