2-bd start at around 500 EUR/month utilities included, but can go higher if you choose a good location and bigger apartment. For 600 EUR you should be able to find a solid one, with luxurious ones in good location starting at 750 EUR/month.
Good internet speed, friendly people, european culture, quick flight or train ride to anywhere in Europe, pretty girls.
I'd explore all these, may be do a few months stay in each city, that would be really cool experience you could tell stories about.
Btw if you go further east check out Chernivtsi, it’s a hidden gem in the East Carpathian mountains.
Bucharest was fine. The lack of decor started to wear on me after a while. Cool thing about Romania is that you can rent pretty easily and leave with one month's notice even if you signed a one year lease. A decent 400 SQ ft studio in Bucharest or Cluj (the most expensive cities) won't be more than $350 a month.
Language wise, most people under 30 had some basic English, I spoke almost no Serbian at all but still managed to get by at stores and restaurants. Internet is cheap and widely available.