Pros:
The pin positions are changed every couple weeks, giving the course a lot more variety than most courses have. Some of the holes (like #4) are completely different depending on the position. The course flows naturally, and you won't need a map to navigate. There are two sets of concrete tees per hole. For some of the B tees, they're just farther back or off to the side (1, 6, 8, 9, 12, 17) and others are entirely different approaches (3, 4, 5 a few others). The elevation changes aren't huge, but somehow the course makes great use of them. Every uphill shot requires you to also throw under a lot of tree branches to get a decent second shot. In general, this is a course that will punish your shot if you throw nose-up (as any good course should). The third hole has a unique tee shot over a grove of trees along a creek that forces you to throw either a hammer or an anhyzer. There are a couple grip-and-rip holes (#7, 10, 11). Despite the challenges, this is a pretty good place for beginners to learn the game. There is no frustrating rough, no itchy undergrowth, and it would be pretty difficult to lose a disc here.
Cons:
This is the most crowded course I've played. In the summer, you will find at least one group on every hole unless you're coming on a weekday morning (I went on a Friday at 9am recently, and it was empty). The lack of etiquette can be frustrating. I've had discs land at my feet on a 250-foot hole while I was putting because someone decided to tee off a little early. I guess that is part of the growing pains of disc golf. At least the course is popular.
The pars on the signs are slightly arbitrary and definitely too high (a 275-foot par 4?). Pretty much every hole would be a par 3. The signs are old, graffiti-covered, and not very helpful anyway (it's not clear what the distances refer to since there are at least three pin positions used on many of the holes, and they only list distances to two positions). Due to all the traffic, the grass is worn away around all the tees and basket positions, so the place gets awfully muddy after a rain.
Other Thoughts:
This is the best course in the Omaha area in the winter (the only one that is consistently playable), and in the fall and early spring it's not as crowded as the summer. If you want to introduce some players to the game and don't mind a leisurely pace, come to Seymour. If you are accustomed to a bit more solitude and peace, this might not be the course for you. Seymour shows what a strong disc golf community has sprung up in Omaha and demonstrates the need for several more courses. Fortunately Cunningham is open again and Hummel Park will hopefully open soon.