Brahimi is proposing elections for Syria. The discussion at the moment seems mostly about the question whether Assad and his supporters should be allowed to participate.
I seriously doubt whether elections are a good idea. To solve an armed conflict one needs a compromise where both sides get something they want and where each sides also gets guarantees that it will not unfairly treated in the future.
It is not hard to see what both sides want. The most important thing for the opposition is safety for its fighters. They don't want to be arrested and tortured. Next they have some economic wishes: an economic policy that pays more attention to the agricultural sector and an end to crony capitalism.
The side of Assad will want something similar. No "war crimes" persecution aimed at punishing anyone connected to the government while leaving anyone connected to the opposition off the hook. Safety from violence for regime supporters and members of minorities in rebel controlled/opposition majority areas.
The secular character of the Syrian state will be a hot point for both sides.
You cannot expect honest voting when for many people it is a matter of pure survival. We have seen in Ivory Coast how this can go wrong. There the opposition won according to the results. But according to the government supporters this was because in one opposition controlled area there was massive fraud. The West simply ignored these complaints and did an armed intervention to bring the opposition in power. Hundreds of thousands ended up in refugee camps in neighboring countries. Given the election fraud in Egypt and the well known aversion of Salafists against democracy it seems to me rather optimistic to expect fair elections in Syria.
For Syria you have in addition to wonder what the value of elections will be when the Assad side is not allowed to participate. It is well known that millions of Syrians prefer Assad above the rebels.
My preference would be a government of wise men who are acceptable for both sides. They should oversee the integration of the rebel fighters into civil life and the reform of the police and the army - cleaning them from torturers and making them more inclusive. Such wise men would need good diplomatic skills. They would need to convince both hard-line Assad supporters and hard-line rebel leaders that they are the best alternative.