A lot of (perhaps even the majority) of grood movies are based on books. Also there is s a growing trend of making pretty decent movies based on comics. Therefore, spin offs are not automatically doomed to be lame. The biggest problem, i think, is that movie studios don't take video games seriously enough yet - the general attitude is "it's for kids, throw in a few half-assed CGI effects and it will do". But if comic books broke through this barrier, certainly it is possible for video games.

In Vampire: Bloodlines on a certain main story mission the next level would fail to load when it was supposed to. Thankfully, the workaround was to open the console and enter a command to load it manually at the right time. Still, having to google a workaround to progress is bad. I know, Bloodlines technically was developed by Troika. Still, mostly the same crew.