I would play it.

If they want to make a profit they should go for it, but they probably should've done this earlier and stopped with the deceptive MS exclusive first party-ish marketing with MS. Sony should say no to this game and yes to Titanfall.

They can keep it.

id pay 50 cents, honestly. 

Sony should sure as shit not say no. there might be gamers out there who might want to play it, it doesnt make sense for sony to say no to games being released on their platform. as far as what cryteck did, it was the best thing they did, MS marketed the game a lot, and it sure as hell needed it. if MS didnt back this game up it would have sold a lot worse than it did now. 

I doubt PS4 owners are open to buying Ryse on PS4.

We already know that developers who own their IP are eventually free to take their games to other platforms, and we already know Tomb Raider will come to PS4 at some point. As the PS4 --> Xb one gap widens the time between Xb one launch and PS4 launch decreases. I reckon it'll be on PS4 by January 2015. Though it won't be announced until after Xbo one version has launched.

Yeah i doubt that too, but maybe they wouldnt have such problems if the game was on PS4 from the launch

Who is we ? I think a lot of people will be surprised when Sunset Overdrive and TR will come on PS4

Well I will be surprised if SO comes to PS4. TR is pretty much a certainty, it's just a matter of time. MS cannot pay enough (well they can, but they wouldn't) to take an existing franchise fully exclusive, esp when it has recently seen a resurgence on popularity exclusive. The time to take TR exclusive was TR 2013 because that was a risky reboot so it would have been pretty cheapt to do it. But of course who is going to buy exclusivity for consoles that are well past their sales peak and on a rapid decline?

they would need a lot of framerate work,and extra levels/missions(good ones)

If Devs will improve everything on PS4 version, I might think about. I would say yes.