Artificial Intelligence Work in Progress

I've got a broad production level puzzle I've been trying to figure out and I've never been sure if I've been working with all of the pieces. I'll try to explain the problem and my considerations. It has worked well enough. This becomes a "tax" I need to pay, and when I just have a few relatively simple characters, it's not intolerable. Now, I put on my magical hat of farseeing 3, and I see a future where my game has dozens of characters, each with FSM scripts. The overhead tax I need to pay increases proportionately, and it gets to the point where I need to spend equal amounts of time maintaining AI scripts as I do with building out game systems, which ultimately slows down the pace of development. Here's where I get a bit conflicted.