Re: Orochimaru, Kabuto, Tobi and Sasuke
Kabuto had surpassed Oro. So basically his ideals were the same as Oros. He wanted to accomplish the same things, and he got even further than Oro (or so he thought).
I don't think Kabuto cared any bit about Sasuke. He only said that, to make sure Obito didn't doubt Kabutos loyalty.
Kabuto wasn't loyal to Obito. First of all, the seal to release edo tensei, he lied, when he told it to Obito.
Secondly, Kabuto showed that his true goal, was to capture Naruto for himself in the war. This would totally go against Obito. Also he didn't fear Obito, since he had Madara.
So basically, Kabuto has his own purposes to take action in the war, what exactly he wanted to do with Naruto, is hard to tell though. He wanted too many things. Itachi, Madara, Naruto, Shisuis eye, Sasuke, etc.. Doomed to fail
Your thing about Oro fusing with senju DNA is quite good tho! Sadly Oro didn't know that his experiment didn't fail, till he met Yamato, and it was only shortly after that, when Sasuke absorbed him. So all in all he was too busy training Sasuke to be able to move further on that part.