There were tons of incredible games that were out on the PS3, and some would even look so much better on the PS4. Which games do you want for to be ported or in any other way brought to the PS4 if possible? If you don't want any to be ported, why not?
I know that Tomb Raider decided to go ahead and take that risk (Tomb Raider: Definitive Edition), turned out to be successful-ish? I'm crossing my fingers for The Last of Us and GTA V to be ported :D
Playstation Now is not enough. I feel like PSN reduces the possibility for some games to be actually ported because they might put it on PSN and the developers would decide not to port the game because you can already play it on PS4 on PSN however for a limited amount of time :(