I like variety so I did a similar route. First day from Porto along the ocean on the board walk, then the central route to Pontevedra where I turned west on the Spiritual route loop (that includes a boat ride) to Padron where I joined the crowds for the final day and half of walking into Santiago. After that it was a beautiful 3 day walk to Finisterre and 1 day walk to Muxia and then a bus back to Santiago.
If you can, stay flexible and let what's happening around you (weather, people, places, feelings) guide you. If you budget a few extra days you can take advantage of this flexibility. I had heard that walking Porto to Vila do Condo can be unpleasant if it's very windy (rain or shine) so check a forecast just before you leave your Porto accommodations. I had decided ahead of time that I wanted a shorter first day (20 - 25 km) walk to insure I didn't over do it on day one. Thus I had decided to take public transport to my starting point on the coast if the weather forecast was favorable and if not, then public transport to my starting point on the inland route north of Porto, avoiding some of the less interesting city walking. I had a relaxed breakfast and at 9am checked the weather and the coastal route had a sunny, warm and light winds forecast so I took public transport and got dropped off north of Matosinhos but south of the Boa Nova Lighthouse and enjoyed day one walking with the beautiful sand, sun and surf constantly filling my senses.
I was not planning to take the Spiritual loop and actually made my decision to do so when I arrived at the turn off. I was starting to yearn for a less busy walking path so I spontaneously took it. I had done some research before the trip about the Spiritual Variant and the highlights everyone talked about was staying over at the Monastery. Although it sounded like a great experience it wasn't enough to sway me during my planning stage and it sounded like reservations were required several days in advance. I'd also read about the boat ride to Prado that did not excite me and many reviewers said it could be uncomfortable if you got the very exposed 12 passenger boat due to rain, wind, cold and fog since it leaves early in the morning. I thought that was the boat I signed up for but it did not show up on time and about an hour later a larger boat showed up that took about 25 of us onboard and it was tightly packed but had walls, windows and a ceiling. It was cold and wet and a good thing the little boat did not make it. They try to make the boat ride interesting but it isn't. There are various crosses on the side of the river and clam farming going on and they serve hot tea at one point in a dixie cup while we are all sitting on top of each other. I did appreciate the effort but the biggest benefit to me was the boat ride replaced almost a full day of walking, so I stayed on the same walking schedule as the rest of my camino family who I had met along the way that had stayed on the main path and I was able to rendezvous with them all at noon the next day in Santiago.
I had given myself a buffer of 2 days for the whole trip but did not use them and I budgeted 3 days to walk back to Santiago from Muxia. I arrived to Muxia during a blustery day that included a few storms that blew over me, sunshine, clouds, extreme winds, rain, calm, warmth and cold...it was one of the strangest weather days I have ever experienced. The next 6 days was a forecast of storms and lot's of rain so I took a very early bus the next morning to Santiago, then a bus to the airport where I figured out where to go next to use up my remaining days before my flight from Porto left for home. I ended up going to Barcelona via Madrid. It was a much better idea than walking 3 days in the rain and sitting for 2 more days in Santiago. I also got to experience some of the most intense protests in Barcelona in October of 2019 which was interesting from a cultural perspective. It also had the benefit of being able to peacefully stroll down the middle of some of the busiest roads because they were blocked off from traffic. Barricades were set up in advance in the morning providing a park like experience when walking because the protestors mostly came out in mass later in the day. Make the best out of whatever happens and stay flexible. Bom Caminho