umm dude. i m not a tyre guru but ima tell you this. i have teh same model with 15 inch alloy's and yokohama tyres. and i am telling you that the ride is screwed.
I suggest you keep your orignal 13 inch tyres and rims. 14 and 15 take the joy out of this car.
If you want, and if you are in lahore, you can pm for my number and test drive my car before you make purchase. infact, if you still want to go to 14, you can have my 15 inch new rims and tyres for free if you give me the stock rims and tyres.. (im not kidding)