Another show I have actually seen some of (the first 7 episodes).
Legend of the Galactic Heroes is, according to vague recollections that seemingly can't be backed up by any evidence I can lay may hands on, based on novels by Yoshiki Tanaka, which in turn were based on a Traveller RPG campaign he ran. It's the Traveller RPG bit I may be wrong on, the novel thing is well documented.
It is Space Opera, with emphasis on the Opera. A massive cast, with intricate plots filled with political machinations. This is a show where characters are introduced with a subtitle telling you who they are so you can keep score at home.
It tells a tale of a huge intergalactic war between the Galactic Empire and the Free Planets Alliance. But unlike, say Star Wars (a major influence) neither side is the “bad guys”. There are equally reprehensible people on both sides (normally the older characters), and likewise honourable folks too (normally the younger characters). It's the sort of show whose fanbase is fanatical about it and so while it's not potentially got that big an audience, for many who have seen it, it is their favourite show. This is borne out by the fact it is technically an OAV having been released to video before being televised.
I first got interested in it through some episode guides in the late, lamented V-Max magazine, eventually picking up a fansub tape from the old, old, anime club in 1999/2000. There are now digital fansubs available, but the sheer size and the fact I have other lengthy shows unwatched mean I've not been tempted to start again with it. From what I've seen though, it has a lot to offer in terms of writing. Animation wise there is little to write home about however, being merely competant. And design wise is variable, it's origins show through early with some pilots shown dressed almost exactly like the rebel X-Wing pilots from Star Wars.
There are also episodes uploaded to Youtube, in fact I struggled to find just an OP clip amongst the episodes uploaded. Here is the 3rd opening for the show.