Better yet, why don’t you do the following:
1: Use HSReplay to track all your mulligans over 1000 games and see what the data shows.
2: Use HSReplay to track your early round draws over 1000 game and see what the data shows.
3: Use a spreadsheet to track this over 1000 games and see what the data shows.
I actually did #3 on a smaller scale. I played 10 games with no Vipers in my deck and then 10 games with 2 Vipers in my deck. I actually faced more weapon decks after I added the Vipers, which is the opposite of what you suggest should be happening.