Having come back from there, I can sense that Estonians are super friendly compared to the girls of Latvia (some exceptions of course) and they receive less stags. Lithuania feels the same but Lithuania is even less invaded. The cities are also smaller than Riga and I don't feel they can accomodate as many tourists. Didn't get the feel there were many sex touristsin Estonia, some backpackers and a lot of Estonians and finnish girls to be seen in pubs. There is a lot of finnish people there. The estonian girls were super nice and would join us on our pub crawls.
In order of friendliness: Lithuania--Estonia-------------Latvia
In order of friendliness: Lithuania--Estonia-------------Latvia