Madscientist, ALL, i repeat ALL masterpiece RPG's are unbalanced. About PFKM, you can beat the game on normal or even on easy with pure RP builds.
When i finished for the first time, i picked a silver draconic sorcerer and learned ZERO fire based spells which means that i lost Fire Snake and sirroco, both are the best mid tier spells in the game. Except on house at edge of time which is much more annoying rather than difficulty, i had ZERO problems with a pure RP build. I even had awful low DEX meaning that i can't exploit the brokenness of sneak attack + ranged touch attacks in the game and had no problem.
Ed: I was going to include "a warlock without a patron" but you know... nwn2
Warlock power can be obtained via bloodline. Some people love to push warlocks as "clerics 2.0" BUT
That is not the case since 2e. They LEARN from their patron and get their soul "infused", they don't get spells like a cleric. In fact 2e had rules to clerics and paladins losing their powers but the worst thing that can happens to a warlock is, quoting the The Complete Wizard's Handbook
"The Witch kit cannot be abandoned. If a Witch manages to sever all ties with the entities responsible for her instruction (usually requiring the power of a wish or its equivalent), she loses two experience levels. (...)
PS : I hate rule butchering but one rule alteration that i liked is that on DDO, they made part of your eldritch blast damage being force and part whatever your patron instructs you. Fey = sonic, GOO = Acid, Fiend = Fire. Each damage type also has a save. Fey has the less resisted damage type(sonic) but the worst save(reflex). And DDO Black Tentacles are great. Aren't good to grapple as P&P(which has CL + 8 AB) and the duration is just 10 seconds, but the damage is ludicrous high compared to P&P. HEre is a link https://ddowiki.com/page/Evard%27s_Black_Tentacles
