"Do you think catholic priests should be allowed to marry?"
I suppose that's the Church's business, and the Church's decision. I think it's ridiculous, but I'm not Catholic.
"What is your interpretation of the biblical reasoning behind it?"
I honestly don't know what the reasoning is, Biblically speaking. My understanding is that there is precedent for it in some of Paul's letters, although I feel the precedent is only there if you want to see it that way. I also don't feel that something Paul wrote to Timothy should be the basis for anything at all. Then, again, I'm not Catholic.
"Do you think if priests were allowed to marry, it would affect the religion in a negative way?"
Nope. Don't see how it could, if the myriad Protestant denominations are any indication.
My overall understanding is that priests were not forbidden to marry until the First Lateran Council, in 1123. So, one has to ask, what had changed?