My concerns:
1. Release date? This matters because I have time now to play. No idea whether this would be the case come next February or March.
2. New best builds for Scum? So far, I am liking the Scum style. I like how the Scum actually make secondary weapons highly viable again. Don't know about you, but I rarely see secondary weapons other than HLC near whether I live. But with Kavil, the Y-Wing title, and other newly revealed cards, secondary weapons can actually be quite strong now. However, I do not know what builds will wind up being the best for the Scum. Wouldn't want to buy a bunch of Scum, only to find out that some units are barely playable. This is especially since I don't know most of the fluff behind the Scum and have no time to learn the fluff, so I only play Scum for the gameplay and not for the story (I.E. Unit Strength is very important). This is in contrast to the Empire, where I am cool with getting a TIE Advanced because, hey, it's Vader.
Because of these two concerns, I think I will play by ear and not order any Scum until they have actually been released.