Having seen Trezeguet wanting to do good this summer and seeing some results coming from him, I'd say we should definitely go for Krasic.
Sure, Dzego is a great striker but he would cost us too much, meaning we wouldn't be able to invest enough in other areas. A good plan of action would be to get Krasic at a wise price to solve our midfield problem and spend the rest on someone good at the back. I am confident that our strikers should do well, given that the resulting midfield works well to get the ball where its needed at the front. Krasic, Diego, Pepe, Camo (given that he doesn't get a red card after breaking someone's leg) and Giovinco (given that he is willing to adapt for a 4-4-2) is a good enough offensive package.