Your results are disappointing as I'd suspected they would be.
The amplifier chain seems ot struggle to make power and the quality
of the power is poor.
What also is suspect is the two IF stage 12 and 45Mhz have excess
gain and the mixers are likely getting over driven. How much excess
depending on how you count it overall at least 16db. I don't believe
that helps except to make up for low gain in the transmit chain.