Sophie is one example of the middle class values she had growing up being turned to good use as a royal. She does not seem to be a "fancy" person inside. Kate, once her kids are older, may be like Sophie in a way, but Kate met William at a much younger age than Sophie met Edward. She'd already had a regular life, education, and work history. In any event, she's a real asset and a treat to watch in action.
In future, more down to earth royals will do better IMO. You see that with Victoria (Sweden). Sophie can glam up (which is good), but she is down to earth and never comes across entitled or arrogant or "too grand". Even the background in Bagshot Park seems normal.