I still hold that typing speed is not the main factor in the time it takes for a project to be completed. If it is, there is a big problem (Weeks of coding saves us hours of planning).
Regarding your question I prefer using the standard layout as it means I don’t have to spend the first 10 minutes looking stupid when presented with a standard keyboard layout.
Some of the replacements you have suggested, e.g. the top row with the special characters doesn’t make a ounce of difference as the outside finger on the other hand should be moving to shift at the same time.
IMHO One thing that helps above chaining layouts is using only keyboard shortcuts. Vim and Emacs are recommended. It makes moving text around far faster.