As far as tread goes, I'll let a manufacturer (Schwalbe) do the talking:
Why ride a slick tire?
Even in wet conditions, on a normal, smooth road, a slick tire actually provides better grip than a tire with a tread, because the contact area is larger.
The situation is much different on a rough road and even worse on a dirt trail as in these cases the degree of control provided by a slick tire is extremely limited. A slightly serrated surface on the tire tread can have a positive effect on tire grip, as it creates micro interlocking with rough asphalt.
You can decide which conditions pertain to you but remember that your average amateur racer rides thousands and thousands of miles on regular streets and many of them are on slicks.
Racing tires that often come stock on road bikes have two problems. The first is flat protection and the second is durability. They often grip pretty well because they're made of a softer compound but that makes them less durable, - they'll wear out faster.
Better tires often have multiple compounds so that they can provide decent grip without wearing out quite as fast. They also have flat protection. Top tier racing tires can actually make for an enjoyable commute but they don't last and they're expensive.
There's been some good suggestions already but another tire I like are the Vittoria Zaffiro Pros. While they aren't as light as a racing tire they still roll pretty well, will last reasonably long and aren't super expensive.