I don't have the same experience as everybody but my take on this:
Romania: Never went
Greece: Lot of people during summer in Greece, in August Italians have their vacation. Maximise your potential by going to islands where specific countries fly to (for example, swedes fly to Rhodos, canadians and aussies to Ios...)
Moldova: Never went
Ukraine: Supposedly Odessa is quite busy during summer...similar to Budva.
Serbia: Belgrade was dead mid-july when I was there..the splavs were empty (weekday). Lot of people party in Budva and Montenegro.
Croatia: Early July was quite busy on the coats, especially in Split. Zagreb was busy too.
Albania: Can't comment.
Hungary: Busy in June, July and August...lot of foreign partiers but also lot of Hungarians...festivals (Sziget Island), Balaton Sound.
Austria: Vienna was more or less busy end of june.
Slovakia: Bratislava was dead early July...pretty boring city...however the few slovaks we met were still at university (their semester was not over) and they were quite eager to meet new people.
Poland: Maybe not so busy howver I had very good experience in Warsaw and Krakow during summer.. need to try the busy months..but not as dead as one would expect.
Russia: Cannot comment
Belarusia: Cannot comment.
Lithuania: Vilnius is almost dead during the week but there is not many tourists and the few Lithuanians that will go out will be friendly and eager to meet foreigners.
Latvia: Very bad, most tourists guys were men...girls go out but are afraid of guys. Busier than Vilnius in summer.
Estonia: Very good during summer in Tallinn, lot of tourists partyers (finnish girls) and easy to meet locals who liked to party with tourists.
Finland: I went in May and it was miserable weather but easy to meet girls on the weekend.
Sweden: Best during summer (early august) early september when university starts its dead during the week and weather is shit.
Norway: Cant comment
Slovenia: Very good country to go early June, Ljubjana was busy and not touristic...university still ongoing.
Paris: Extremely busy, lof of tourists girls, french go in vacation early august usually but are replaed with tourists girls.
Budva: Extremely busy in July and August..probably in June too.. lot of Serbians and Russians go party and to the beach there...however hard place to game.
Romania: Never went
Greece: Lot of people during summer in Greece, in August Italians have their vacation. Maximise your potential by going to islands where specific countries fly to (for example, swedes fly to Rhodos, canadians and aussies to Ios...)
Moldova: Never went
Ukraine: Supposedly Odessa is quite busy during summer...similar to Budva.
Serbia: Belgrade was dead mid-july when I was there..the splavs were empty (weekday). Lot of people party in Budva and Montenegro.
Croatia: Early July was quite busy on the coats, especially in Split. Zagreb was busy too.
Albania: Can't comment.
Hungary: Busy in June, July and August...lot of foreign partiers but also lot of Hungarians...festivals (Sziget Island), Balaton Sound.
Austria: Vienna was more or less busy end of june.
Slovakia: Bratislava was dead early July...pretty boring city...however the few slovaks we met were still at university (their semester was not over) and they were quite eager to meet new people.
Poland: Maybe not so busy howver I had very good experience in Warsaw and Krakow during summer.. need to try the busy months..but not as dead as one would expect.
Russia: Cannot comment
Belarusia: Cannot comment.
Lithuania: Vilnius is almost dead during the week but there is not many tourists and the few Lithuanians that will go out will be friendly and eager to meet foreigners.
Latvia: Very bad, most tourists guys were men...girls go out but are afraid of guys. Busier than Vilnius in summer.
Estonia: Very good during summer in Tallinn, lot of tourists partyers (finnish girls) and easy to meet locals who liked to party with tourists.
Finland: I went in May and it was miserable weather but easy to meet girls on the weekend.
Sweden: Best during summer (early august) early september when university starts its dead during the week and weather is shit.
Norway: Cant comment
Slovenia: Very good country to go early June, Ljubjana was busy and not touristic...university still ongoing.
Paris: Extremely busy, lof of tourists girls, french go in vacation early august usually but are replaed with tourists girls.
Budva: Extremely busy in July and August..probably in June too.. lot of Serbians and Russians go party and to the beach there...however hard place to game.