I'm going for an 8. I don't think there were any really duff stages. When Wiebes took sprint stages she often had to do a hell of a lot of work to get there, so no gentle meandering through sunflower fields behind a break.
The jersey changed hands a lot. We had a highly memorable Ventoux stage. We had some controversy*. We had an exciting finale with a worthy winner crossing the line in yellow.
So all exciting stuff. I don't think comparing it directly to the men's tour is all that sensible as they're entirely different things. I think this stands on its own as a great event.
Eventually, I think it would be good to extend it maybe to two weeks or 12 days + a rest day, but this would only be feasible if (a) it works financially and (b) if the rest of the WWT season includes more meaningful stage racing. Otherwise extending it would just turn it into an endurance slog that most riders are unused to and the racing would end up being really conservative.
* Sadly, the world of social media being what it is, Celia Gery ended up getting death threats. Now, we all know that they came from overweight who still live with their mothers, sitting posting in their pants, so not to be taken seriously but it must be pretty hard for a 20 year old in her first tour.