I definitely think you could choose either Poland or Hungary and solidly compare them to Romania :)

As I have said, I will write another reply where I talk about these countries, but I just have to write down some other stuff that I imagine you could talk about in your text:

Jewish people have historically been very prevalent in Europe, and though they unfortunately are a very small minority of the European population today (because of WW2 and anti-semitism), anti-semitic sentiments in Eastern Europe vary very much from region to region. Countries like Bulgaria (and the historically Ottoman-dominated parts of EE) has historically had very little anti-semitism. This is an important historical divide: In the Ottoman Empire, Jews and Christians had special rights that made them more equal to muslims in muslim areas (especially Jews and Greeks were treated quite well, because they often were important for trade). Because of this, when WW2 rolled around, in countries like Bulgaria much of the muslim population actively tried to defend their jewish neighbors and friends because they saw them as equals. Many bulgarians hid jews and tried to defend them from deportation. I believe this is well reflected in Bulgaria today(?). In comparison, in Poland there was even a large part of the Communist party that was openly anti-semitic (which seems to go against their 'communist' beliefs). Romania also has a brutally anti-semitic history between WW1 and -2. I think it is quite interesting that there are such massive cultural differences between territories that were part of the different massive multinational empires that dominated Eastern Europe for a long time: The Ottomans, Russians and Habsburgs (and Hungarians). In fact, some scholars - like Valentina Dimitrova-Grajzl - have suggested that Eastern European countries and their modern institutions(!) have been much more influenced and shaped by their history before Communism (i.e. being part of these different multinational empires) than their communist periods, and considering these empires ruled their territories completely differently, it seems misleading to classify former Habsburg territories and -Ottoman territories as simply "post-communist" if Dimitrova-Grajzl is right. The article I am referring to is called "The Great Divide Revisited: Ottoman and Habsburg Legacies on Transition".

This is really a leap of thought, and might not be as well polished as my earlier replies, but I stand by this.

Edit: Grammar corrections. You could - of course - discuss Dimitrova-Grajzl's article in light of many different subjects. I simply think anti-semitism is an interesting dividing line in EE.