If 4BB tends to get more than 2 callers, I'll go higher.
if im openraising, i want callers. a smaller raise will encourage re-raising. table texture issues aside, i think 3.5 is about right. do you vary your openraise by posn? i believe in increasing the raise in relation to position. ie, utg 2.5-3.5, progressing to say 4-5x button.

?