Is it correct to say, "Co si dáš k pití?"
Yes, you can say that. The meaning is basically the same, but I have tried to come up with some literal translations to show you the difference.
Co si dáš k pití? = 'What are you going to get to drink?'
Co chceš pít? = 'What do you want to drink?'
How about Co pít chceš ?
That is very strange. It strongly stresses the verb. Use the neutral word orders and deviare when you have a specific reason to use a different order. I could imagine some synthetic situation to use it, but it is not natural.