Just a thought, Reniaa. Would the Jewish festivals be considered as part of the "law"? Are they an obligation or a celebration? These festivals, at least four recorded in the Hebrew scriptures, certainly would not be considered "pagan". There are also no scriptures contemning the practice. We know that Jesus celebrated at least one Jewish holiday before he died.
http://www.mfa.gov.il/MFA/Facts+About+Israel/People/Jewish+Festivals+in+Israel.htm
http://www.jcrelations.net/en/?item=925
Yet the JW's only have one (two if you count the convention). Don't you think the Jehovah's Witnesses are markedly deficient in holidays, celebrations, and festivals, biblically speaking? I'll forgive you if you don't know what you are missing. But I suggest there is a fundamental need for human beings to regularly celebrate. I've mentioned an example above on how it marks the positive memories of childhood.
I am also reminded of the testimony of an extreme cult in Australia, where there was no marking of days one from the other. The children were raised in endless monotony. I was impressed that an adult child recalled very few details or incidents from her childhood. For her, it was one big blur of sameness.