Games are like elegant ecosystems. Everything that is added or removed can disrupt the balance of the ecosystem. DoD is like a super complicated one (permadeath being a huge case on this, because of the possibility of losing your 'work'). Now skills. Probably one of the biggest attractions in this game - creating and building your character. The problem? Some skills seem to be quite unbalanced (for better or for worse). What I find wrong in what trees: Assassination - This was a big boy some time before, but now it has fallen in grace. Why? Well, since a lot more skills have appeared in DoD since the vanilla incarnation and it has been overshadowed by skills like Clockwork Knight (more on that later) and etc. Also, in vanilla there was just Blackjack, Sneaky Shiv and Et Tu?. Adding skills can actually nerf the tree. From an economic point of view - skill points are limited, meaning that more skills aren't always better. And this seems to be the case with Assassination. Slim Customer is, what I call, a placeholder skill (like, for example, Sword Lore - it's not that great on its own, but the next skill is fucking awesome.) and Assassination is already gimped as it is - not a lot of stats for completing the tree and Et Tu? scales with Magic Power? Wut? Also, I dislike Venomous Infusion. Possible fix could be remaking the tree into a highly offense focused tree, with a capstone that makes crit damage scale with crit chance (say +0.01 to crit damage per point of crit chance). Unarmed Combat - It seems to not work without taking a ranged skill together. While it's quite similar with weapon skills and dual wielding, this drawback seems to block off the whole possibility of building a purely Unarmed Combat based build. I've seen few successful builds without Archery or Throwing Weapons. This is pretty much the whole flaw of the tree - not enough damage without the other two common choices. Clockwork Knight - While I'm not sure if this is just a Flavour of the Month type of thing, but it seems that this skill tree is used in pretty much every warrior build (along with Smithing and Tinkering). The main attraction is the super high powered rocket, which can crit (at least a part of the damage), is long range and knock backs and can move shit around + adding to some smithing. But basically the whole tree gives both utility and damage in large amounts making it one of the strongest trees in the game - combine it with Magical Law and it's a roflstomp. There's not much to talk about this. Demonologist - I'm not even sure what this tree is supposed to accomplish, It seems cool on paper, but the lack of passive bonuses and that there are lots of drawbacks in this tree, make it really hard to use. I mean, come on, it has a CtC buff that can nearly kill you (-2 health up to 4 times) at early levels. Also, certainly not a 1-point wonder... Big Game Hunter - Generally, not a terrible tree. but the capstone doesn't seem to roll very well with the make up of the build, but a great one point wonder for early game. Butcher is not so bad, but it could use some stats on it. Other skills are pretty good, but I'd exchange Release the Hounds for something else. I'd suggest something with stats and a (chance?) skill that would hit all animals of the same type in the room (Countdown to Extinction?). Archeology - Capstone is risky (as Krongs can make your artifacts worse), This Translation is All Wrong is risky.
I agree with everything but: 1) touch everything, but don't touch my Release the Hounds. It's one of the coolest abilities of the game; 2) Archeology - being risky is not somethng negative, since it can give you really cool stuff too. Btw, there is a work in progress for rebalancing skills.
I haven't tried the last half of the Demonologist tree yet, but the first half can be worth taking just for Celestial Circle depending on your build. Your passive bonuses (good block, huge magic resist, 4 elements) are right there if you can afford the mana to keep it up when you need it.