I chose Phillippe and Mathilde because they always seem so affectionate with one another publicly -- but not in a blubbering way! They seem like a very mature couple who deeply respects each other (not to say the others don't, of course) and who seem very comfortable and relaxed with each other.
I like them all. King Albert and Queen Paola have a deep respect and love for each other, scandals and all. They've been through alot and you can just see the love when the couple embraces each other.
Those who plot the destruction of others often perish in the attempt. ---Phaedrus
Even though I like the 3 other couples as well, I like Philippe and Mathilde best. They're just perfect for one and other. You can see how much they love each other in little gestures, very sweet!
I also think that it's quite romantic -although it's very sad!!- that they really got close to each other when Mathilde's sister and grandmother died, and Philippe helped her through that difficult time.
You can easily see how much they respect and know each other, how they're a great team performing royal duties, both very committed to their country. And of course they're very nice and modern parents!