I have a somewhat similar issues with bitters and defenses - later in the game. It ruined my latest SE game and kept me away from Factorio since 1 will, because I guess i scaled science and production too early.

To get time to expand i manually cleared close nests and built walls, turrets around my base. But past some time (i had artillery and logistic robots researched, and a decent mall automating most structures and military needs) bitter evolution was too advanced for my wall and manually-fed turrets. I was at point of setting up artillery around my base and requester chests for turrets ammo, but I was flooded with bitters.

I think that i scaled too early, kept using coal for too long, or have a poor wall design (ie. should have stopped using turrets).

Is there a good reference post or video on recommended wall setups/turrets types for defense? I have seen posts with nice defense outposts, i am not looking at a mid game main base setup.