With catholicism you're pretty much allowed to make up anything. We just have one god. But that's obviously not enough so we made up the holy trinity, so he/she is one... But also three. And we've incorporated pagan holidays and beliefs. There it fairies, monsters etc, we just call them angels and deamons and such. And you can pray to god... Or saints or whatever you like. There is a process to it. It has to by accepted by the pope and the vatican. And it takes some time. But they're not opposed to contradicting dogma. And don't believe in logic in the first place. So I'd say go ahead... You can simultaneously have gods before and after and at the same time have it the other way around. It doesn't need to make sense. If you're catholic, talk to the pope. He's infallible. Just don't introduce "making sense" to anything. We can't have that with religion.

It's just a few very old books with how people tried to make sense of the world back then, plus a few thousands of years of extra lore added on top, varying politics during the times and a few old men running the business.

Not before literally, but above. Catholics only worship God, but they venerate other figures. Like imagine you want to send a message to the ceo of your company, but you're a lowly wage slave. Do you snap off an email to the big guy himself, or do you ask your manager to pass the message along? Probably the latter. But even though you're going through a middleman, the ceo is still the big boss. Same thing with God and saints.