Base world layout never shifted in the slightest at any level. It was only the actual embark locations that would vary in layout, often by very little, and there was the oddness I had at 3k.
Pretty much yes, parameter value vs. total and types. The later ones raised some questions for me as to what it classes as a metal since the shallow/deep metals disappeared in higher number gens at the location. Though the "stuff" there had been classed that way in .19. Which leaves me wondering if the classifying has been hard-coded to specific types or if it's somehow tied to the "Flux" not appearing in the summary of the location but you can still find it with the finder bug, or maybe the two are connected...who knows? but Toady.
The initial ones I did from 100 to just under 3k (whatever that number was now) were all at the same spot. At that point, I'd become so familiar with the map, that I could literally eyeball and head back there.
To be semi-exact, it was about 4 squares up from where the mountain range on the west side bowed out, or about 7 squares south of the north boundary. Then in the regional view, it was pretty much the southern edge. As long as a settlement didn't take the spot, it was always there.
Heh, I've still got all the saves except the ones where a settlement was on my spot. When i first threw some data together I offered to upload them all to the depot. Some of them have "active" "play now!" embarks and some are abandoned.
Eliminating the ":"? I didn't bother myself, but did my maths manually. But there should be a text to columns option in most spreadsheet software under "Data" (good luck dealing with the ribbon Excel users). Just highlight the target data, select text to columns, specify ":" as the delimiting character, and it splits it into two columns.
No idea about one biome. I have thought about rerunning everything at a different location, but we got some initial data and a theory and most people seem to have moved on. Getting more data and getting into the nuts and bolts of it would be great in some aspects.
I'll admit freely I wouldn't mind digging into all the info. If it wouldn't drive me mad from boredom, I'm tempted to carefully experiment with every single parameter until I understand their impacts fully, particularly since the wiki info on advanced world generation parameters is kind of meh...
Right now, I'm just enjoying playing .21 and digging in and collecting cobaltite. Don't know yet what I'm going to do with it and a major river, but I'm going to do something (unless another update rolls along or I screw up so horrifically I abandon in disgust). So far those two items have been the only things that cause me to abandon.