Hi, Elaurel, I have often wished I could bring over some of my friends here in the US to show them what the camino is like, and the Camino to Finisterre and Muxia would be an excellent introduction, IMO. Not too much ascent, good infrastructure, nice towns, views, etc. My only hesitation would be the distances that a 4 day walk would require -- not for you, but for people just starting out. In the "standard" stages to Finisterre and Muxia, the days look like this:
Santiago-Olveiroa (21) - Negreira (33) - Finisterre (33) - Muxia (31) (substantially similar if you go to Muxia first).
If you had the flexibility, breaking up the walk either into Finisterre or Muxia into 4 days gives you more manageable stages. Other people have posted suggestions on how to do that, and if you look for some of Margaret's posts (mspath) you'll find some good ideas. The 31 between Muxia and Finisterre would be a long day maybe but as the last day walking I think even inexperienced walkers can push through assuming they are basically fit. There's also an option to break the Muxia - Finisterre segment into two with a stop in Lires. Lires has a few casas rurales, etc, and is about 1.5 km from a beautiful little beach with nice paths to explore. But that would make your 4 day walk a 6 day walk and I don't know if you have the time.
October can be rainy, but it can be warm and sunny. I also think that the warm temps over the last few decades have been pushing further into Oct/Nov.
Buen camino, Laurie