I think that part of what keeps Londo sympathetic is that, for all that he makes terrible choices and goes to some dark places, he's not doing it from self-inte

I think that part of what keeps Londo sympathetic is that, for all that he makes terrible choices and goes to some dark places, he's not doing it from self-interest. He wants to do what's best for his people. In a weird parallel with a later highly-regarded genre character, he actually has a lot of similarities with Zuko from Avatar the Last Airbender. Particularly in the whole arc of rejected chances to do the right thing.