the reason for the limitations in Romania is in part due to the lack of official up to date VFR maps
The limitations can be found here
Cerinte AOA I had my Seneca based at Baneasa for a year. VFR are often limited to below 1000 ft, especially around Bucharest.
Constanta is indeed well kept with friendly staff.
Arad can be a point of entry with often Avgas (although i always flew direct to Baneasa) , but check before you start.