If you're just using the car for fast/enthusiastic street driving then the stock calipers are fine. The biggest problems are usually the pads and fluid. Also, due to the age of the car, the flexible brake lines (a rubber composite) may have also deteriorated to a point where they destroy brake feel. To that end, a changeover to stainless steel braided brake lines will help.
However, if you had just rebuilt all components, then the best advice I have for you is to use hot street pads. If you're in the US, I highly recommend Porterfield R4S pads. They have a website here:
http://www.porterfield-brakes.com/
Their pads are not the cheapest, but I do believe in "you get what you pay for". The R4S' that are in my car are used daily, and I don't switch them out on track days. They perform beautifully in both applications with almost no fade to speak of while on tight, brake-intensive tracks (e.g. Laguna Seca or the Willow Springs short track).
Finally, never underestimate the importance of removing brake fluid from your system once a year, or once every two years at the very least. Brake fluid is hydroscopic, meaning it absorbs moisture. The older the fluid, the more water it has. This contributes to brake fluid boiling over during hard runs up and down a twisty mountain road. It also contributes to sponginess in your brake pedal. Neither are desirable!
For some Milano/75 owners here, brake fluid replacement happens every time we go to the track (that is, if we don't want any brake problems!) so our cars generally have new fluid all the time. This is easy to overlook in daily driven street cars but it doesn't diminish the importance in keeping your brake fluid fresh .... you keep the oil fresh in your engine, you should also keep your brake fluid fresh.
If you REALLY want to spend the money, there are many ways to do so and we'll gladly help you spend yer hard earned cash! In the meantime, however, a new set of good brake pads, stainless steel braided lines and fresh fluid (DOT3 or DOT4 is good enough) will definitely improve things.