The worst things in communism were:
* Not to trust in people near you; everybody could be informer of the "Securitate", the political policy. It was dangerous to criticize the policy of the Communist Party or the fact that you couldn't find food in stores, or the political leaders. In fact it was dangerous to criticize no matter what.
* civil rights were not guaranteed by the Constitution, which was only an empty text
* The interdiction to travel across the "iron curtain". It was possible to travel only in communist countries and than, only if you had a lot of papers from a lot of "important" organizations.
* Not to find food in stores. In 1980 Nicolae Ceausescu decided to pay the external duty of the country not with money but with food, actually with our food. So buying a pack of butter or 10 eggs or a kilo of oranges after an hour’s long line was a real victory for us! So sad...
* To find only "politically correct" books
The advantages were huge only for the aristocracy of the politicians: houses, special stores, travelling and so on. Actually I don't know too much about them, I belonged to the other category.
But for normal people there was the sentiment of the security of the work place. Everybody had to work, there were no unemployed, even if the system was artificial and the economy was not productive.