Let’s describe to the folks at home what the mathematics have to say about this. You open your Hearthstone and you see that Hero 2 has 3.50 placement and Hero 3 has 3.62 placement and Hero 1(PAID) has 4.24 placement and Hero 4(PAID) has 4.62 placement metrics.
That means that the Firestone developer (a great person by the way (go support them)) is telling you that:
Hero 4 (that you can’t choose unless you pay) is the best choice
Hero 1 (that you can’t choose) is ~8% worse
Hero 2 is ~21% worse
Hero 3 is ~24% worse
To see the level of ludicrousness to call that unimportant: the best players in the world (on any game) seek even for 1% advantages so 8% alone is a gigantic advantage and 20% advantages reach the point of just being game-breaking good.
PS If people saw percentage differences instead of just the metric on their screen they would get that more intuitively just as they get more intuitively in standard that some netdecks have higher winrate under certain filters.