Couldn't really tell you, it's scattered all over the place, honestly. The wave sizes and such are in a chart that I posted a while back, but I'll include it again here. You need to multiply the AI Progress x10 in this chart. And for the actual wave sizes, on some of the levels (6 and up, I think) you also need to start multiplying them x2 or more. So it's pretty out of date in a lot of ways, honestly.
I don't keep track of all the little tweaks for the various difficulty levels because they are so spread out, and because it's just something I decide as I go through each tactic: at what level can people start handling this? I'd have to go through a few thousand lines of code to find all that out at this stage, and I'm not sure how actionable that information would really be in general. Sorry!
