Why is the migration from Stack Overflow only allowed to those specific sites?
Yes, these sites are closer to programming, but IMHO, TeX - LaTeX and SharePoint are rarely used; for example, the Server Fault, Programmers, Code Review are the better options to choose.
Maybe this list should be a read from the user's preferences.
Sharepoint - 127 - 1% rejected- I hope that it was not the main reason to include the site to this list :)