As an individual housemate, I think I like Priya the best, for seeing the game as we see it. Katie seems much weaker, which is probably good for Priya as this will make her easier to manipulate. Inevitably there will be a rearrangement of the housemate pairs, so it'd be interesting to see whether this could work in Priya's favour to be paired up with somebody ballsy enough to play the game alongside her without worrying about pleasing the other housemates. Would she work best in a team with somebody weaker than her, or somebody equal to her?
I did like something about the pairing of David and Sandra though... I got the impression they will function well as a team, and they seemed likeable, but this is after one night, so I could quite easily go back on my word within the next 24 hours.