You got all the advice there is to give, so here is some peice of mind. Three of the four The hardest traps to get happend to be in this type of tiered run. Party level 5-7, you are a 5. Deleras part 1 is level 5 (6 on hard.) Necro is level 8 (9 on hard.) So you were a level 5 rogue working on a level 9 trap box.......... This is also a problem for levl 3 rogues in the last part of tangle root (level 7 on normal) and wickedly hard for level 6 rogues in the second to last part of C06 (level 9 on normal.) A Cabal for One (level 13) is the only tough trap box for the sake of argument that is tough..............but for the other three 'hardest to get in the game trap boxes' it happens alot as the adventure scales, your skills become overmatched. Happens to every rogue that plays the game with aggressive quest selection.......ie tangleroot at level 3/4 instead of 6/7.

Second the idea of droping the feats for rogueing.........your giong to want two weapon fighting chain or a variety of other fun stuff to spend precious feats on.