I'd take Uchiha. The chance to awaken sharingan is too much of a boon. I'd become a genius, able to learn anything be seeing it once. The clarity of perception is also nice. I could take in the most minute details as long as it is within my field of vision. Not to mention the perfect accuracy. And then their is the real nice stuff. I'd be able to mess with people's heads to no end. I could control them, make them see anything I want them to see and make them experience whatever I want them to experience. If I was a pervert(which I'm not), I could put women to sleep and have my way. I'd even be able to mindf*ck my enemies. And all that and more is possible without mangekyo.
Being a Senju would be nice, but the only one with could power, Hashirama, is just a one off, a freak occurrence. A normal senju would be physically strong, and not super human strong either. I'd live longer, things would be less dangerous thanks to my durability, I could heal faster, but that is about it. Not bad, but not good either. If I could have Hashirama's powers though, everything I just listed would increase, and I'd be able to make anything out of wood. Thing is I'd have no way of knowing if I'd be a Zetsu, a Yamato, or Hashirama. So I'm going with Uchiha.
