Currently there is nothing you can screw up in the game, no builds nothing like that.
Aside from one thing: FEP
The FEP system currently allows someone to level their character incorrectly, Say you were to eat only cow sausages for the first few days as you learn the ropes, now each stat will cost you a few hours to get a point in.
What about those who spend their time leveling one stat like Strength due to the lack of use in any other stat? They will be screwed even more.
Why not have each stat have its own FEP bar? Or even allow a player to set FEP into different stats for different values, so 5 points of strength FEP might be exchanged for 2 points of con FEP?
Anything is better than the current cost system.