I think except the debatable areas of Macedonia there are no serious confrontation between Slavs and Greeks, we have a lot in common and we still have common enemies.

I thinks so too. I just wish for Greeks and Macedonians to find a solution for their confrontation. Macedonians have to decide whether they wish to be Slavs or ancient Macedonians and Greeks have to realize that portion of ancient Macedonia is now Slavic and that Slavs in that area use the term "Macedonian" to describe their nationality since no Greek would do so now. There are several other Slavic nations today that took the name of non-Slavic tribes, neighboring Bulgarians are a good example. 

Pan-Slavism as Slavic nationalism is not anti-Greek, IMHO. Greater Albania project, neo-ottomanism are just some of the problems Greeks and Slavs need to solve together.