Godfinger and other Jakobs sniper

[Horoai]

I must be doing it wrong.

Jakobs sniper rifles with a better color-rating than green seem exceptionally rare but remarkably unimpressive in return.

Playing as Zer0 I have only found two blue and two purple jakobs sniper (unlike pistols - I can wipe my ars.e with blue to e-tech pistols) and it seems like they are rare for no good reason. As the wiki states blue jakobs sniper are supposed to deal more damage than green with a much lower RoF.
No surprise the trade is never worth it in terms of DPS but the difference in actual gun damage seems insignificant. Get a 2 level higher green one and you're even. Purple ones don't lack that RoF but apparently don't deal any more damage either.

So I thought to myself pearlescent and legendary will be the way to go then. Wrong.

I found a skullsmasher and a godfinger. I compared them to green jakobs sniper rifles of the same level and the difference in damage wasn't that much most of them time. Infact, it was a negative difference in favour of the green weapon quite often.

The obvious reason is that both weapons have very specific conditions if you want to unlock their damage potential. For a skullsmasher you'll have to fight very close quarters which means perks like kill confirmed become useless for the most part.
The Godfinger on the other hand required me to keep an unreasonable (and on many maps even impossible) distance while it practically forbids the use of velocity. That way One shot One kill is less reliably which in turn ruins my DPS again.
Bottomline is they don't perform very well on average/ in common situations and don't utilize Zer0's perks that well in comparison to green rifles.

What the hell am I doing wrong? Is there something I don't get or is green jakobs really already the best thing I can go for? D: