I don't like the Solar faction because their alliance with the Blood faction seems very fragile. Both the description of the clan itself and the effect of the Sinhai amulets imply that the leader is not the most reliable person. They might stab us in the back.
The Blood faction pays very generously. It's possible that this is because they can't help any of the other two factions, which offer benefits in addition to gold. The quest will probably involve somehow taking advantage of the conflict between the clans or escalating it in some way. And then exploiting their weakness. But there might be something else too. There are definitely hidden dangers, like this "undesirable information." And I think Delhi could really mess things up for us. Overall, the quest seems quite dangerous.