Place the balsamic vinegar and honey in a small pot. Bring to a boil, and then reduce to a simmer, stirring often. Simmer until the mixture is reduced by approximately half, stirring occasionally. The balsamic mixture should be slightly thick and syrupy, although it will thicken a little more as it cools. Remove from heat and set aside until zucchini is cooked.
Slice the zucchini into rounds on a slight diagonal, about ½-inch thick.
In a large bowl, toss the zucchini with the salt and allow to sit for 15-20 minutes. Drain the zucchini, and then toss with the oil, black pepper, and red pepper, if using. (I like to mix with my hands to make sure that the oil is evenly dispersed among the slices. Also, if you are in a hurry, you may skip the draining stage, although I find this enhances the texture of the zucchini by removing a lot of moisture).
Heat the grill (or grill pan) to medium-high. Cook the zucchini for five or six minutes on the first side before flipping, and then cook for another three to five minutes on the second side. The zucchini should have nice grill marks on each side and be tender but not mushy. Note: Leaving the slices undisturbed while cooking will produce nice grill marks.
Arrange the zucchini slices on a large plate or platter. While the slices are still warm, sprinkle with the crumbled goat cheese, and then drizzle with a few tablespoons of the balsamic-honey syrup.