Coming from a Perl 5 background, what are the advantages of moving to Perl 6 or Python?
There is no advantage to be gained by switching from Perl to Python. There is also no advantage to be gained by switching from Python to Perl. They are both equally capable. Choose your tools based on what you know and the problem you are trying to solve rather than on some sort of notion that one is somehow inherently better than the other.
The only real advantage is if you are switching from a language you don't know to a language you do know, in which case your productivity will likely go up.
I know Perl 5. What are the advantages of learning Perl 6, rather than moving to Python?