I've been trying to find an intelligence build that not only works in single player, but also doesn't fall behind other players in multiplayer, and I can't seem to get one to work. Where most other builds have a means to gain xp, even gathering jobs can gain xp from gathering resources, intelligence builds who construct traps or craft tools can't keep up. Add to the fact that higher quality tools simply break less often but aren't more effective, and now they have no edge on any task. Finally, because a heavy investment into intellect is required for most tasks there, and there are no survivability perks or combat perks there that can't be easily replaced by some other action, intelligence builds tend to die a lot, especially in multiplayer.

In short, advanced players need Intelligence, but starting out with Intelligence is not viable, even in multiplayer.

My first thought on how to fix this was to allow the player who places a trap to get a small amount of xp from the trap for every durability point lost to a zombie, but this might not be possible, nor might it be a good solution.

Another solution I just thought of was rather than tie each talent to a single stat, have it require X stat points from it's "Primary" and "Secondary" stats, where the primary provides double points. Give each skill 1 primary stat (where it currently sits) and 2 secondaries that you can sub in at reduced effectiveness, and now players can branch out more, but are still better rewarded for paying for the actual stat it falls under when trying to meet a specific skill's prerequisites.

Some examples: (Double current stat requirements for the required amount of stat points for each. This can be adjusted as needed)
Forge skill: Primary is Intelligence, Secondaries are Strength and Fortitude.
Reasoning: To make a good tool, you need to know how to work the metal, you also need the strength to bend it, and the endurance to work constantly it before it cools.

Deadeye: Primary is Perception, Secondaries are Fortitude and Agility.
Reasoning: In the military we have a mnemonic for firing a rifle: SABT = Steady Position, Aim, Breathing, Trigger Squeeze. These are the 4 things you need to fire a rifle effectively. You also need to be able to see your target, which is why Perception is primary. Steady Position is about aiming, and Breathing is about Fortitude to be able to control your breathing.

Sexual Tyrannosaurus: Primary is Strength, Secondaries are Fortitude and Agility.
Reasoning: Using a tool efficiently can be easily done by having enough strength, but having the fortitude to work longer and agility to use the tool more efficiently can substitute for some amount of strength.

Do this with every skill, and you have a better skill tree that can be adjusted with more granularity. It also helps intelligence builds, because their intellect helps provide available skills elsewhere now, at a reduced rate, and makes them more effective in combat or for resource collection. This also ends the need to really focus on one main stat until you have everything you want from it, spreading yourself out feels less meh.

For displaying this, I would replace that ugly lock icon that you have to hover over for a tooltip with the relevant info, and just put the info there. X/Y points required and below it, put the first letter of the two secondary stats that contribute (P S F A I) The primary stat is the stat page it's on always.

e.g.

8/14
F A

Do this instead of the lock, so people can in one glance see what is required, rather than have to find a pop up menu that just delays information.