i would like to throw in
optimization Floor (or suitable replacement meaning same thing)
~0 has so many trap options that system mastery is needed to know what not to take on accident.
~1 has several glaring trap options shoved in its face that don't work well unless you know how to work around them.
~2 while it has several trap options most of them come from the basic series of trap options, very few cater to the class directly.
~3 the only trap options are the ones designed for use by all classes (IE run, 1H0S fighting,)