These are all tested by me and others and seem to be accurate on the effects. Some settings can be confusing, but most are pretty straight forward.

Day Time Speed - How Fast Day Passes.
1 = Default.
.5 = Half Speed.
2 = Double Speed.

EXP Rate - How Fast You Gain XP.
1 = Normal exp gain.
.5 = Half exp gain.
2 = Double exp gain.

Note: Any action that would reward only 1 xp can not drop below 1 xp, such as gathering sticks.

Pal Capture Rate
1 = Default.
.5 = Twice as hard.
2 = Twice as easy.

Pal Appearance Rate
1 = Normal.
.5 = Size of pal spawn groups will be reduced, only spawning 1-2 in a group.
2 = Pal spawn groups will be doubled creating big packs, including bosses.

Damage from Pals Multiplier
1 = Default.
.5 = Pals deal ½ damage.
2 = Pals deal double damage.

Damage to Pals Multiplier - Incoming Pal damage multiplier.
1 = Default.
.5 = Pals take ½ damage.
2 = Pals take double damage.

Pals Hunger Depletion Rate - How often pals need to eat.
1 = Default.
.5 = Pals get hungry ½ as often.
2 = Pals get hungry twice as often.

Pals Stamina Reduction Rate - How quickly pal stamina depletes.
1 = Normal rate
.5 = Pal stamina depeletes ½ as fast.
2 = Pals run out of stamina twice as fast

This setting mainly effects mounted pals.

Pal Auto HP Regeneration Rate - How fast pal health regenerates after not taking damage for a time.
1 = Normal rate.
.5= Pals regen HP ½ as fast.
2= Pals regen health twice as fast.

Pal Sleep Health Regeneration Rate - How fast pals regenerate health from sleeping or being stored in the Pal Box.
1 = Normal rate.
.5 = Pals heal ½ as fast.
2 = Pals heal twice as fast.

Damage from Player Multiplier - Each players outgoing damage.
1 = Normal.
.5 = Players deal ½ damage.
2 = Players deal double damage.

Damage to Player Multiplier - Each players damage taken.
1 = Normal.
.5 = Players take ½ damage.
2 = Players take double damage.

Player Hunger Depletion Rate - How often do players need to eat.
1 = Default.
.5 = Players get hungry ½ as often.
2 = Players get hungry twice as often.

Player Stamina Reduction Rate - How quickly each players stamina depletes.
1 = Normal rate.
.5 = Players stamina depletes ½ as fast.
2 = Players stamina depletes twice as fast.

Player Auto HP Regeneration Rate - How fast player health regenerate after not taking damage for a time.
1 = Normal rate
.5 = Players regen HP ½ as fast.
2 = Players regen health twice as fast

Player Sleep HP Regeneration Rate - How fast players regenerate health while sleeping
1 = Normal rate.
.5 = Players heal for ½ as much while sleeping.
2 = players heal for twice as much while sleeping.

Damage to Structure Multiplier - Base building objects incoming damage multiplier
1 = Normal rate.
.5 = Player base building take ½ as much damage.
2 = Player base buildings take twice as much damage.

Note: This setting can be BRUTAL. Especially on wood bases with raids enabled. One bad move from you, your pals, or the invading enemy can lead to an instant base wipe.

Structure Deterioration Rate - How quickly base buildings and objects lose durability over time.
1 = Normal rate.
.5 = Buildings deteriorate ½ as fast.
2 = Buildings deteriorate twice as fast.

Personal Note: If you are just trying to relax, have fun with some friends or are new to survival crafting games, don't be scared to set this lower. No one is going to judge you.

Maximum Number of Dropped Items in the World - How many dropped items can exist before they despawn.
3000 = Default.
0 = Dropped items will despawn immediately, including mob drops and resource nodes.

Note: A higher item limit will impact client/server performance.

Gatherable Items Multiplier - Gatherable items group spawn multiplier
1 = Default
.5 = Gatherable items yield ½ as many resources.
2 = Gatherable items yield twice as many resources.

Gatherable Objects HP Multiplier - How much health gathering nodes have.
1 = Default.
.5 = Gathering nodes take ½ as hany swings to harvest from. (But you will get half as many resouces)
2 = Gathering nodes take twice as long to harvest from.

THIS ONE IS IMPORTANT!

Note: Changing this setting on an existing world wont effect existing nodes until they are gathered from and then respawn. The amount of resources and exp are not effected, only the amount of damage, or number of swings with an axe or pickaxe which are needed to get the resources from the node.

The more swings you need to do equates out to more durability loss to your tools. Some other survival games make it to where the longer you hit the node for the more resources you will receive. Not THIS game, with a metal pickaxe you'll get roughly 120-122 ore from a node. This just determines the number of swings one would have to take to gather.

Anything set below 1 will give you less resources but you will also need less swings to gather said node. Also this currently seems to only affect wood and not stone.

Gatherable Objects Respawn Interval - How quickly gatherable/harvestable resources respawn
1 = Normal rate.
.5 = Resources respawn twice as fast.
2 = resources respawn ½ as fast.

Dropped Items Multiplier - How much loot is dropped by pals/enemies.
1 = Normal amount
.5 = ½ as much loot
2 = Double loot

Time (in hours) to Incubate Eggs - How long eggs need to incubate before they hatch
1 = Normal rate (1 hour for largest egg).
0 = Eggs hatch immediately.
72 = Largest eggs takes 72 hours to hatch.

Enable Raid Events - Player bases can be subjected to random hostile NPC/Wild Pal raids
Yes = Npc raids will occur
No = Npc raids disabled

I would wait to turn this on until you familiarize yourself a bit with the game. I have been base wiped from low level enemies due to use of fire and water pals not putting out blazes like you'd hope they would. You can always disable or enable this later if you change your mind.

Death penalty - What items will players drop on death
Drop all items = Default (you will drop your full inventory and have to go back to retrieve it.)
Drop all items and pals on team = You will drop everything including your pal team on death
drop all items except equipment = You will drop your inventory but not your equipped items or pals
No drops = You won't drop anything when you die.

Max number of guilds - This is actually number of players per guild.
20 = Default

There is a max of three player bases per guild, and if you're just playing co-op with friends you'll have to level up your bases individually OR one of you can hit the cap and it will count towards the guild before you can be in the same guild due to limitations of number of allowed bases. This won't affect you if you're base building together with one Palbox, but separate bases will have to wait until you level up a bit.

Example: If I am high enough level to have three bases, I can then invite two other friends to my guild who have their own bases and they can join the guild. If I have three friends and only two bases available for upgrades, then only two of us can have our own bases.

This mainly applies to co-op since server may be able to set settings differently.

Max Pals Working at Base - Max number of pals that can be deployed at a single base
15 = Default amount
20 = Max

Note: That if you are hosting a co-op server, and you have this up to 20 your computer may suffer on performance a bit.

If this guide helped you than please feel free to award and thumbs up this guide!