I have my main bus paved with both concrete and brick (brick under belts, concrete everywhere else).

Would it be possible to add a toggle to not replace brick or something like that?

I'd agree with this... I place a lot of brick around... preferably, I'd like brick under everything I place, extended 1 space out, so if I have brick under a 3v3 assembler, the brick covers a 5v5 space.

Ideally, I would like a method where I could specify which types of paving go under which types of constructions, in a priority list... so, I could use the danger-marked concrete under/around my power generation, and have it auto-updated as I change things... so if I expand my coal-steam generation, eventually the paving beneath will be expanded to cover it, or if I remove it to relocate somewhere else, eventually the caution paving under the old location, eventually gets removed...

There is a lot of room for growth with this kind of mod.

Perhaps also a different type of building, say some kind of antenna, which will control the paving area (in a radius instead of a square)

I want to keep the mod fairly simple. When it comes to doing tricky stuff like bricks under belts, how would you recommend setting this up to tell the script where to place bricks and where to place concrete? Is there any advantage to using bricks instead of concrete (besides savings)? I could change the mod to not replace brick, but I think that would reduce the advantage of automation. I could add a hotkey toggle and leave it unbound so it doesn't get pressed accidentally. I think I'll do that.

This mod won't overwrite existing concrete so if your power BP includes hazard concrete (or colored concrete) that won't get replaced.

For people dropping by, this has now been implemented in 0.9.3: By popular demand, concreep will not auto-replace brick.

I'd like concrete in logistical areas and stone in construction areas