Full disclosure, I have not taken the tour you’ll be on but have visited Lisbon several times on my own. Looking at what’s included and the itinerary description for the tour, I would suggest many of the sights that Diane did.
During the RS tour city walks, you will no doubt see some wall murals and also encounter the fancy McDonalds in Porto. The tour probably does not ride on any of the trams funiculars or elevators (Lisbon, Porto, Coimbra), but I do suggest doing that on your free time to experience the excitement and of navigating their very steep hills and narrow streets. It’s fun - be aware on Lisbon tram 28 though; sometimes pick pockets.
Along with the tile museum, check out the coach museum. I really liked viewing all the many fanciful horse buggies and coaches in Lisbon.
For Porto, if you will be going to the Gaia port houses, I suggest looking online for some of the more popular houses and book your English tour ahead. When I went in the later afternoon, the English tours were booked. Of course, you can visit the port houses and have tastings without a tour but if you are at all interested in port wine and how it becomes port, a tour is nice. I took the water taxi from Porto to Gaia but I believe you could walk across the Ponte Dom Luis I bridge. Coming back from Gaia, after disembarking the water taxi, I stood in line for the funicular that leaves from the Porto Ribeira area to arrive at the top of the steep hill, saving me some energy. Maybe this is TMI, but I wanted to give you some ideas on how to get around Lisbon and Porto.
Have fun on your tour - I wish I could live in Portugal.