I like having to chose one path or another when building a character. If I take ranks in this skill, I wont be able to take that skill ect. This game doesn't have that. I can spread out across all three classes, and I do. Nothing wrong with that it's like multiclassing in DnD, 14 fighter / 4 Sorc / 2 artificer is a perfectly valid build... probably... somehow; I digress. I would love to see something added to this game that would force us to make a meaningful choice that would make our characters unique.
My idea is a simple one. I propose adding a new row of skills at the bottom of the skill tree. The five skills in this row would have 1 rank each and would grant us a very cool very powerful ability, but the catch is you can only take one and the other 4 permanently gray out at least till you drink a respec potion.
This would be your capstone Perk.
3 rows 5 perks means 15 new capstone perks on the tree and since it would take 19 skill ranks to unlock each one you could theoretically have for example a capstone in Warrior and a capstone in Engineer, but you'd have 19 skills on each tab to do it meaning you'd have basically zero skills in the Arcanist tab.
Something like this could lead to a lot of wildly different builds.