@jkd69 I'm going to suggest the opposite of my dear walking buddy...
@maggiec ... she's right in that the Sanabres is stunning but if I had 10 days I think I would start at the beginning.
You get to see Seville, a few great stop-off points on the first day, you also get to see a variety of terrain and animals... the flowers were starting to come out last week so it will look incredible. You would certainly reach Zafra, and beyond if you walk fast/far?
This is the start of my blog from Sevilla
https://caminobrassblog.wordpress.com/2016/09/20/finding-the-arrows/
The VdlP is beautiful and I think which ever section you decide on you'll have a fabulous walk
p.s. my second choice might be Merida to Salamanca? This site might help with your planning
https://www.gronze.com/via-plata