Your list is definetly playable, depending on your goals (and $) you might swap some things but as a beginner you´ll have fun with it.
What else do you have? Maybe we can tune your list without spending any money
The Destroyer actually is a rather bad Jack.
I´d get the upgrade Kit and get Black Ivan instead. Rat 5 has some value, Rat 4 doesn´t.
What you might lack would be a dedicated armor cracker in case your feat isn´t enough. I´d recommend the Great Bears of Gallowswood, they are cheapish and you´ll use them in a lot of lists.