Yes.
I would probably use much shorter average. 2-3min tops. Instead boot the base up as soon as i get into the field and after other gear is out and after few minutes of warmup, when the base has passed the cold start, i would start the average. I dont see any point using long average time as long as the base shows you are in the ball park and do not jump all over the place (max 10-15m)
Other then that it seems you have the basics all sorted out. Well done.
You could, but since you log raw data back at base you really dont have to. As long as you remember to turn on logging.
Yes. But also remember to note the base coordinates when you do the RTK in the field. Take a picture or a screenshot of the base coordinated used.
When you have done the PP of the base, you need to apply the same shift you get from average base and PPK base coordinates to all your captured points from survey. This is done in e.g a spreadsheet.
Here i did the shift for another user. As an example