yes i too hate boolean merrly cos they work like 1% of the time an the rest they just screw up

i like to cut holes this way (other than just deleting the faces)

use create polygon tool or a primitive shape and place it band on/next to the geometry delete the faces
now use vert snap (the verts on the boder edged of the hole) and snap them to the new geometry u created this way u get the shap u wanted then just delete the new geo ans tweak the verts on the border edges

thus is very help ful wen u wanna make circle holes in ur geo as ull know that the verts r in the right place to make a perfect circle