Answer

Absolutely not. I have said and written more than once that if they were to renew the Sanhedrin in our time (not like the ridiculous jokers who did this in the past, but for real), I would move to Australia. That is because I have no trust whatsoever in the people who would presumably staff the Sanhedrin from among the rabbis of our generation. So I also assume that it will not be renewed, because there are no suitable people—or at least those who would serve on it would not be among the suitable ones.
When the generation becomes fit and there are suitable people, then of course it would be proper to renew the Sanhedrin and restore our judges as at first. In that case, the Sanhedrin would know its place and its role, and would know what to intervene in and what not to. The question of separating religion from the state would not arise, because the public as a whole would be religious and would accept the system upon itself. Without that, there is no place at all for a Sanhedrin.
In such a situation, the Sanhedrin would not be a fourth branch; rather, it would be the legislative branch (perhaps alongside a secular legislative branch, according to the model of the Ran regarding the law of the king).