Well, choosing this is like picking your favorite kid :) The quick answer is "I love them all".  But really, the decks we use most often are the green and blue 10th anniversary decks.  The colors in this deck turned out really well and we too prefer having a bird in the midst.
The variety pack includes our latest green and blue 10th anniversary decks and the Candy Colored deck as well as the Colorblind deck.   All decks are fully plastic and long-lasting.
There is actually a very easy way to pick up the plastic cards.  See:
The easiest way to clean your cards is to take a warm damp cloth and wipe the cards clean. The cards being fully plastic can be completely submerged as well.
Yes. The cards are the same size as the regular rook playing decks.