Here is what we are trying to say:
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Are the commas correctly placed? How else would you fix this sentence?
I would suggest
[Note the shift in the placement of first, for clarity.]
I think it would be just fine if it were:
Pretty much, just get rid of the second comma, I don't believe that it is necessary.
To answer your commented question, yes, you can use a second comma. (Was just stating it wasn't necessary, not that you couldn't use it.)