Maxwell series GPUs from nVIDIA are expected to be very power efficient. High performance with lower TDP. You can wait for that. But really, changing the GPU now won't do any good to you.
switching from 8350 to 4770k just for gaming just isnt worth it but if temps are your problem then liquid cooling is probably your best bet i have a msi gtx 780 twin frozr 4 and it does pump out quite a bit of heat
it will cut down some but just remember if you put an ac unit to close to the case condensation can form if the temps are that bad its time to invest in some long cords and move the case to another room where temps dont matter