For me, it would be Mr. Darcy from 'Pride and Prejudice'. His complexity, intelligence, and eventual transformation make him incredibly appealing. Plus, his loyalty and deep love when he finds the right person are truly charming.
I think I'd go for Peeta Mellark from 'The Hunger Games'. He's sweet, loyal, and always there for Katniss. His love is selfless and that's something really special.