Hate it when games want the player to pick skills before they are at least somewhat familiar with the game. What is the ratio of locked doors/containers to hackable computers?, How do the rewards and hidden content behind them compare?, How good is melee versus ranged?, etc.. This pretty much guarantees your character customization will be uninformed in the first playthrough, and the story will be spoiled for potential future playthroughs.
I know what you're saying, but that's just the minmaxer in you that needs to be reined in.
Years of playing RPGs and strategy games are directly responsible for the yearning to optimise and the annoyance of playing blind. There was a period in my gaming 'career' where I wouldn't start a fresh new RPG/strategy without reading up on it a lot or watching decisions pro players make on YT. Where's the dump skills? Which items seem like junk but become useful later? Many RPGs have some weapon classes that are simply inferior to other options, should I go with swords instead of axes? It kinda fuelled a hate for arbitrariness some of the video game design systems have. Invest in the wrong skills, you're gimped. Sold that item? Too bad cause 3 hrs later there's an NPC asking for it. Picked the 3rd choice at a branching moment? Too bad, cause the two others offer rewards that would've been much nicer to have considering your playstyle, etc etc.
At the same time, there's something really off with games that offer ways out (like RPGs with respecs), or are designed around each choice being equally good. There's something very fun and exciting about choices being final, and even about having to make the most out of a poor skillset/item selection/unit roster. Respecs just cheapen the experience and make your choices seem irrelevant since you can do a U-turn at any moment and just completely switch your build around. The 'balanced' approach can be even worse.
In principle, I agree with PoE's design. In practice, I found that I much preferred the BG series' approach of "here's your character, make the most of his skills and deal with his limitations" as opposed to the game being fine with you doing most things with most classes. It rendered most of the choices regarding building characters and decking them out totally void of flavor and excitement.
Seems like you might be on the same path so my suggestion is - leave the optimal build for your 2nd playthrough and enjoy the game blind, and try to make the most out of the resources you limited yourself to with your poor choices. Lots of fun to be had that way! And if you do want to keep on optimising, have you tried playing roguelikes? Cause that's a genre that openly welcomes pursuit of the games' systems best (ab)use.