Mainly looking at Aracana, Stealth and Mechanics I guess. Don't think I need to worry about anything else as I can have other party members do those things. In POE1 I'm easily getting away with a 5 in stealth.. (with gear boosting it to 8)… I can sneak / steal / scout around quite easily. No idea if that's sufficient for POE2. Mechanics obviously need to be the highest. Have no idea how much skill boosting gear there is in the game for mechanics. Arcana is the one I have no idea about. How