The story is long (obviously) and intensely philosophical. There are jokes but they're either without humor or simply not funny, so if you're looking for something light look elsewhere. As far as character development goes there's a huge ever-developing list of people to keep track of and this is where it gets a little tricky. Since it is so obviously taken straight from a book, Legend of the Galactic Heroes is no more than a collection of conversations. Even the action sequences (which are still extremely intense) are portrayed through dialog rather than karate. Since we have such a huge sample of each character's thoughts and ideas it's very easy to become attached to them while being exposed to different ideologies and political viewpoints.
While it is an extremely stimulating piece of futuristic fiction it is also quite entertaining. However, it's less the type of entertainment you'd get from Stallone blowing stuff up and more the type you'd get from Anthony Hopkins delivering a monologue. Sure, both are great but you might not be thrilled by Hopkins as much as by the concrete shattering antics of Stallone.
In any case, if you're looking for something that is fairly slow paced but can keep your interest and give you something to think about go for Legend of the Galactic Heroes.
