I have been using my bendy ruler to see what sort of crotch curve I have - its sort of like measuring an armhole to see what a sleeve cap should look like though so definitely interesting. I don't do too badly imaging things in 3D so I'm hoping all this thinking will make progress simpler later.
My crotch curve is longer than the ruler. 27" front to back of which 16" is at the back and 11 at the front.
The back is shaped like 2/3rds of a U, very rounded but the front is a smooth shallow curve. It a very strange looking thing with the two together. I think it is worth tackling this part first and then looking at the legs after that.
Comparing it to a Burda draft, the back is sort of in the right shape but the crotch needs to be another 2" deeper!
The front crotch curve needs to be shorter in the rise and deeper by an inch and a quarter, that's another 3.5" I need in depth - wow. Mind who cares what the pattern pieces look like if it fits.
I shall have to process that a bit as I am stunned. May add pictures tomorrow.