In 2009, Romania had a referendum for reducing the Parliament size to a maximum of 300 seats. However, it was never implemented and in fact, the number of the seats increased to nearly 600.
This article shows a Europe chart about number of representatives per million people. Romania has indeed one of the largest index (29) in Europe.
Question: is there an official recommendation for number of representatives in an European democratic country (e.g. EU country)?
I am thinking of something like Venice Commission type of recommendation.
This study suggests that an optimal number of representative might exist:
Having too few members of parliament means parliament is likely to be un-representative, but it seems that having too many makes it easy for vested interests to buy influence. Simple logic suggests that the optimal number of MEPs should be proportional to the square root of the population. Empirical work suggests that nations with a much higher number of MEPs tend to be plagued by red-tape and corruption.