@Borris: I have NEXEN 2000 rotational 175/60/R13 installed to my Mehran and it boosts exceptional grip and handling. Its a Soft tyre and helps in making the ride smoother. Though my car does not yet have Alloys but the performance overall bcoz of the tyres change is very very much noticable. Very much recommended. Cant technically reason my recommendations though, i just liked the look of these tyres when i bought, but now i m loving the ride.
Braking altogether is a different issue just like in Corolla XLi/GLi which has problem in braking. Mehran also has a problem in braking which can be rectified by getting a booster installed which works as an apmlifier for brakes. Costs around r.s. 4000 [around r.s. 3000 for parts from Bilal Gunj + around r.s. 1000 for labour].
Keeping in mind that the installation of boosters tends to alter the original car which may result in voiding of warranty etc. Though I have not yet installed this booster but I have heard it works very well for Mehran's hopeless brakes.