Kind of the same answer as Ebok, but basically: if you have a burning idea for a Front already, by all means create it. If not, there is no reason to do so -- you don't really need to worry about Fronts for the first few sessions of the game, and there is no need to rush into them.
You could definitely think a little bit about Threats, though -- like take a moment to think about each NPC that you know about so far, and ask yourself what their deal is. How might they threaten the PCs? That sort of thing. I wouldn't worry at all about forcing any decisions, but if something jumps out at you while you're thinking about it, by all means start building some ideas around that.