Let me ask you a question. If someone wrote you long letters about God and, when you read them, the only God they are mentioning the whole time was the Father, would you think they were defining God any differently than the Father? That's what the Bible is like. With Paul's exhaustive defining of God as the Father, he wasn't trying to hint about a different god. Just go with what Paul said, don't add to it and argue against him, and you will see clearly who God is.
So what you are proposing, likely to preserve your beliefs, is a fallacy called an argument from silence, i.e., "Paul didn't say Jesus that Jesus is not God, so we can't rule it out." is the same thing as saying "Paul didn't say God is not a cheese pizza, so we cannot rule it out." The scope of Paul's writings involved defining who God is, not in refuting all of the possible heretical teachings that were abounding The letters are just about getting the truth out there. I would like you to read the first few verses of all of Paul's letters please. Do you see how he opens every letter with saying God is the Father?