the 1st Killzone needs to be remade, because the story of the franchise has gone downhill. They should remake/reimagine the 1st one while having the feel of KZ2 in mind. Shadow fall open areas were nice, but it felt like if it was other IP and not KZ; also the story sucked.
The 1st game was very ambitious, so with all the tech an experience they got they can make it a Masterpiece.