Good question. But let me clarify one thing: are you suggesting that:
A) Individual Saints replaced individual Roman gods - like a St. Apollo becoming patron saint of light, for example? Or
B) that the overall concept of Saints, as understood by Catholics, seems too close for you?
If it’s A, can you be more specific? Assuming it’s B, I’ll say this. The Early Christians, in the catacombs, inscribed “Peter and Paul, pray for us” into the wall. Petitioning saints in Heaven. And why were these Christians in the catacombs in the first place? Vecause they refused to worship false gods.
There are two ways of violating the prohibition against having other gods in the Bible: the first is proclaiming something besides God as god. The second is holding something ABOVE God. Protestants often imagine a third category (honoring someone more than they deserve, or honoring someone similar to how we imagine ancient pagans might have worshipped), but that third category is unbiblical. Catholics think that the Saints work only through the power of God. It’s the difference between magic and miracles. To a non-believer, it may look like Christianity, with God, the Light of the World, and abundant miracles, is just warmed-over paganism, with a sun god and a abundant magic.
In fact, athiests tend to point to ancient pagan gods, and claim Christianity is modelled off of it. But you and I both know that those similarities are only surface-deep, an that Christians can tell the difference between a god of light, and the True God. Light of the World, Jesus Christ. We can also tell the difference between Saints and gods, and between Saints and God.