Wow, I was actually right about Malack. I can't believe it.
I'm going to go out on a limb here and predict that the next death with be Geoff. I don't think they'll leave the desert without the Tarquin/Ian subplot being resolved. Malack already died, so I doubt Tarquin will. I also doubt that Ian Starshine will die. However, Geoff seems to be involved in some dubious stuff, and his fate is tied to the Ian/Tarquin/Bozzok mess. So, I'm betting on him being the next one to bite it.
Carefully reasoned; therefore, undoubtedly, I've just talked myself into a totally wrong opinion.