Interstate 287 is one of the busiest freeways in New Jersey excluding the Parkway and Turnpike. Unlike those highways, however, it maintains a total of six lanes for most of its length. That unfortunately is not enough to handle the capacity of cars that use it. No matter what time of day you drive on this highway, you are bound to hit some congestion. Forget about getting anywhere on this highway between the hours of 7:00 AM and 9:00 PM, and between 4:00 PM and 6:00 PM. It's not going to happen.
Because of such congestion and older sections of the highway in its lower section (south of I-78), safety on 287 is often not good, which leads to accidents and more delays. Once you reach the further north sections of the freeway it gets much newer and thereby better in terms of safety and pavement condition.
Clarity of signing is quite good on the highway, there are often diagram overhead signs showing the layout of an upcoming interchange.
Aesthetics is the same kind of stuff that you would see on any normal freeway, grass median with a few wider forested medians. Again, the northern section (north of I-80) gets much more scenic as the highway cuts into rock walls.
As far as pavement condition goes, the northern section from NJ 208 to I-87 in New York is a smooth concrete layer. The middle section is mostly pavement over an old concrete layer, which sometimes creates cracks in the highway. This section is fine to drive on, but it could use a repaving in a few years. However, the southern section from EXIT 6 to NJ 440 and beyond is in terrible need of repair. The original concrete slabs are extremely worn and cracking, with giant holes missing, which are often poorly patched only making it worse to drive over at high speeds.
I-287 is not the most direct way sometimes, but it's all you have in the northern part of central New Jersey. It is also your only way of reaching the northwestern part of the state. It needs major work, but it serves as an adequate form of transportation at the time being.