What should I look for in a cooking pan for Risotto?
I suggest getting a quality stainless clad saute pan or saucier. For years I made risotto in the All-Clad 3 qt. saute pan shown here:

Unless you're serving huge portions this is plenty of room for 6 servings of risotto. There are larger options available though, including a mammoth 14&quot; 6 quart one.
This pan easily does 90% of the work in my kitchen, so at any price it carries its weight in the kitchen.
That said, this past Christmas I got the All-Clad 3 qt. copper-core saucier shown here:

It's a very close matchup, but this pan is perfect for making risotto. The higher sides are a definite benefit, but you don't sacrifice much in flat surface area. The copper core is amazingly responsive, noticeably more so than aluminum. It's obviously rather expensive, so if you're uncomfortable spending that much on a pan I'd suggest getting one of their regular 3 qt sauciers -- you'll spend at least half as much.
If I only had one pan in my kitchen though, I think I'd still go back to the saute pan above. Its versatility is just unmatched.

Regarding your concerns that a wider pan won't heat as evenly, this is generally true for a cheaper pan. However, All-Clad pans use magic to bond a layer of aluminum (or copper) between a layer of magnetic stainless (exterior) and 18/10 stainless (interior). The end result is a very even heat which you can actually confirm with an infrared thermometer.