1) Max Hp Gain.
The only 'difficult' parts of the game requires more max hp (the final damage spike and seals). Also helps with funneling. This basically makes the game 9% easier.

2) Food Value.
This also helps tank the last damage spike, I'd say this helps by like 4.5%, the 'drawback' is you eat slower, but that actually isn't that much of a problem because the main pain of the game is damage spikes, eating fast/slow has no impact on spikes.

3) Combat Shield.
This will help with funnels and fights maybe 3% helpful, it doesn't help with volcano/damage spikes so not THAT OP.

3) Food CD.
This doesn't help as much as it seems, maybe 1%, at the start decay kills you but by late game decay does nothing so CD is meaningless.

4) Base Decay.
I've read this barely has any impact on anything, maybe like half a percent? Again, decay is meaningless late game.

5) Decay Growth.
I hear this is even less useful than Base Decay, so maybe .35%

6-7) Exp Requirements.
This seems to be actively harmful, it lowers the time you are alive per round leading to less max HP gain, making the endgame harder. Chapter 1-7 will be 5% faster, but chapter 8-9 will be 5% harder, which ultimately I think makes these perks negative 1% useful.. Because of the length and difficulty value of C8-9.

8) Passive Jobs.
Another actively harmful perk. You will get to C8 faster, but then it will pre cook all your food, making seals harder, and making lava and the final damage spike really annoying. Negative 15% rating on this one, avoid at all costs.

Let me know if I got anything wrong, and yes my % values are weird, I tried to keep the full run in mind and not just what that perk was affecting.