I don't think it'd be possible for the Sage to give the Juubi conscious or thoughts. The Rinnegan likely can't do something like that, especially given the makeup of the Juubi. The Sage also likely couldn't tame the Juubi, so he sealed it in him, and the same either probably happened to him what happened to Tobi or the Sage was able to avoid the Juubi taking control due to power.
Since the bijuu were made from the Sage's imagination, he could have put consciousness in them as he would have the power to do so.
---------- Post added at 12:46 PM ---------- Previous post was at 12:44 PM ----------
I just had a weird thought regarding taming the jubi and perhaps the other biju. Recently the manga presented the idea that the uchiha clan developed a special type of chakra when experiencing severe loss which resulted in the sharingan. The sharingan in turn feeds from this hatred and becomes stronger. Lets change that a bit though. I don't think it is hatred itself which feeds the sharingan... it is the uncontrollable love which results in that hatred that feeds the sharingan. So in obito's or sasuke's case it was not hatred for their enemies or the world that made the sharingan stronger, it was the intense, borderline psychotic, love for their family or rin which made it stronger.
Now, the reason I bring this up is because obito effectively managed to tame the jubi.... and in pretty much the same way naruto tamed kurama, he overpowered it with love. So what if the rikudo intentionally set up the sharingan so that love would make it stronger? The sharingan already has the capacity to control biju in itself so it would make sense the rikudo would take things a step further so that the uchiha could become excellent jinchuiriki by having overwhelming amounts of what they need to tame biju. Now, the issue here would be that the plan would have backfired horribly. By making them grow stronger through love he also opened the door for their emotions to tun rampant and with more love they also had the innate capacity to hate more. Which is why obito was able to control the jubi, even if what he had was a sick and twisted love for a dead girl with whom he can never be with.
Well the Sage is a man of mystery. Who knows what he intentionally did . As for Obito, I dont think he *tamed* the beast. I think he just subdued it's power and took it for his own. And yes, I do believe the Uchiha powers do originally come from love. But when they go into a certain state of mind where there extreme trama after the love has broken down, there sharingan awakens. Then as they build up there hate, there chakra also becomes different being more cynical (Like Sasuke when he got itachis eyes)
Taming, subduing... the difference between those is not really relevant to the point I was making. When naruto first got chakra from the kyubi he did so by overwhelming kurama's hatred with love. It was a similar situation with obito. Obito was being consumed by the jubi, we saw that as he was being torn apart by the jubi, however the memory of rin helped him get it together and ultimately to become the jinchuriki.
Now, in this particular case my point is that love never really disappears from the uchiha when he goes crazy. Sasuke never stopped loving his family or brother when he was planning to murder everything, obito never stopped loving rin, madara never stopped loving his brother. My point is that even in their insane states it is love that continues to feed the sharingan. The issue is that with the overwhelming capacity to love those close to you comes the capacity to hate those who hurt them by just as much. So the idea that hate and pain fuels the sharingan is wrong. Hate and pain are simply what is most visible in an uchiha when it comes to such a situation thus it would create the understandable misconception that hatred fuels it. Its not the hatred that goes out of control and fuels the sharingan. It is love that runs out of control and the side effect of that is that hatred increases along with it.
Now, why would the uchiha have such thing? Is it a coincidence that they have so many tools to get biju under control? At this point it seems somewhat evident to me that the jubi is not just the source of the sharingan or rinnengan but also all KG. Think about it, the jubi had an innate rinnengan/sharingan deal and its jinchuiriki is able to use any form of nature manipulation imaginable. So the idea that the rikudo sennin could manipulate to some degree which KG are passed down is not weird at all. Perhaps his original intent was for each of his sons to have a particular purpose in regards to the future and the biju. The uchiha had the innate ability to control biju and their love makes them potentially ideal jinchuiriki at large and the senju are all exceptional considering that the senju were seemingly able to best the uchiha clan and they have invented basically all relevant techniques around (hiraishin, shadow clones, edo tensei and who knows what else). The notion that the sage would want his descendants to be opposites and fight each other is weird though. I think the sage meant for them to complement each other with their gifts however the unexpected side effect of the huge amount of love the uchiha were capable of resulted in them ending up as opposites.