--Jn 3:16 is not the only verse in the Bible that deals with salvation. In examining the 'whole counsel of God' (Acts 20:27) we find that repentance (Luke 13:3) confession (Mt 10:32-33; Romans 10:9-10) and baptism (Mk 16:16; Acts 2:38) are just as essential as belief. Jesus did NOT say "he that believeth only" in Jn 3:16 for such a statement would contradict what Jesus said in Lk 13:3; Mt 10:32-33; Mark 16:16. Since the Bible does not contradict itself, then it must be understood that "believeth" in Jn 3:16 is used as a synecdoche, a part for the whole. That is "believeth" includes repentance, confession and baptism. In 1 Pet 3:21 Peter says baptism saves but "baptism alone" does not save. Here baptism is used as a synecdoche where it includes belief repentance and confession
--Eph 2:9 excludes works of merit from salvation, not obedience. All works are not the same and no verse ever excludes obedience to the will of God from salvation.
--baptism is only for those who are sinners and capable of believing, repenting and confessing which excludes infants.
Can you spell "rationalization"? The Bible clearly says that baptism is a rite after one is saved. It is not essential, it is a "statement" expressing the virtual death of the unsaved person and the virtual birth into the new life.
"John's baptism" in the Jordan River: how many were saved by it? None. Jesus was baptized by John; did that save Him? Of course not.
Luke 3:3, " He went into all the region around the Jordan River, preaching a baptism of repentance for the forgiveness of sins."
Acts 19:3-4, " Paul said, “Into what then were you baptized?” “Into John’s baptism,” they replied. Paul said, “John baptized with a baptism of repentance, telling the people to believe in the one who was to come after him, that is, in Jesus."
Romans 6:3-5, "Or do you not know that as many as were baptized into Christ Jesus were baptized into his death? Therefore we have been buried with him through baptism into death, in order that just as Christ was raised from the dead through the glory of the Father, so we too may live a new life. For if we have become united with him in the likeness of his death, we will certainly [future tense] also be united in the likeness of his resurrection.
Even the few words in one verse in 1 Peter which can be misinterpreted out of context..."And this prefigured baptism, which now saves you—not the washing off of physical dirt but the pledge of a good conscience to God—through the resurrection of Jesus Christ"... it clearly says that baptism is a pledge.
Your error lies in your repeated use of synecdoche to misinterpret what the Bible clearly says -- there are no hidden meanings, or substitutions of parts for the whole. Acts 26:24, " As Paul was saying these things in his defense, Festus exclaimed loudly, “You have lost your mind, Paul! Your great learning is driving you insane!”