From Dragon of Desire:

Also, I noticed that the only passive defense options are the Fence from Open Modular Passive Defense, which zombies will break, and the ICBM spikes and Fire Spikes. I recommend another mod to add in some new stuff, featured on ForgeLab's 100 days in a Parasite Apocalypse video:

https://www.curseforge.com/minecraft/mc-mods/hbms-nuclear-tech-mod-reloaded

And here's the video if you want some inspiration:
https://www.youtube.com/watch?v=pLWiW6E9cPk

However, note the nuclear mod would need a LOT of tweaking. Seems like it adds quite a bit and it wouldn't play nice with what you have. Lotta redundant stuff.

Big thing is the Incendiary Barbed Wire. It doesn't count as a block, yet is walkable so mobs path through it. Would REALLY help.

Also, the Open Modular Turrets are not immune from zombie griefing. Means you can't have them built into the wall with the cool addon where they slide into the block when not in use.