I used to have a favourable view on a sort of "expert government", but I don't think anymore that would actually be much better than what we have now.
In Germany (and I think that's similar everywhere) we already have many experts involved in lawmaking and advising the government. There is the ethics commission and the council of economic scientists for example, and also commissions that are just there for the purpose of "designing" a certain reform (like the Hartz commission). Unions have a big influence via political parties, as has the industry. Legal experts check laws at various stages, when it is first drafted, when it is voted on in parliament, when it is voted on in the upper chamber (which in Germany consists of state representatives) and when it is signed by the president. Then of course you can take the law to court, if you think it's unconstitutional.
All these experts and control instances still produce laws that do not work as intended or are just plain stupid.
An expert chamber would not be democratically elected, and thus while less likely to engage in campaign hijinks, also not democratically legitimized.
Experts, whether they come from the academia or elsewhere have political opinions and biases too. I doubt that they are more "objective" than politicians. (For a German example look at people like Hans Werner Sinn and Bernd Lucke.)
If you don't like that the Chamber of the Lords is not democratically elected, fine. But I don't think coming up with a complicated and balanced system where all sorts of experts constitute a chamber will change much. The opinions and biases are probably not that different.