YI would personally swap the 5D shield for a 4A. The 4A is about 1 million more expensive and uses more power, but it is stronger and allows another 16T of Cargo space. It is a matter of preference but the Python is an extremley versatile ship.
Yes, you are probably right. Problem is, that in my case, the 13.87 vs 14.17 Ly jump make a difference on my favorite trade route. So I went for 5D shield and less cargo. I will probably change this in future.