Revan never really cared about light or dark side. Maybe the preachy, overly light-sided, Jedi brainwashed version of him did. But the real Revan, the one who won the Mandalorian Wars, valued strength above all. He understood that neither side could bring any kind of clarity on its own. You need both perspectives to gain any kind of balance. The Jedi would say that a purely Light galaxy is balanced, but this violates the laws of binary opposition. There must always be light and dark in equal measure. And Revan understood this. As for the question of his death, well.... I believe it would be best if Bioware just left it open-ended. No closure, but also no disappointment (Since Bioware has a long history of offering the latter). Let our imaginations decide what happened to him. Because let's be honest, KOTOR fans probably won't be happy either way. It's the way we are. We do know that HK lived to some degree, at least. I suggest looking on the SW wiki if you weren't privy to this information. So we can take heart that some part of Revan will live on no matter what.... In a homicidal jedi-killing droid that we've all come to cherish.