Basel suggestions

Are you coming off or onto a Rhine cruise? Friends were doing this a couple of years ago, and I suggested spending those 2 days in Luzern. Worked out great. They did the boat plus train to Rigi Kulm mountain top. Then to Engelberg to see the high Alps. They bought Saver Day Passes and all transportation was covered.

I see from your other posts that you will have 8 days in Switzerland before your cruise. I suggest only 1 night in Basel. 2 nights in your choice (Montreux area or Zermatt), 3 nights in Berner Oberland, 2 nights in Luzern.

I was in Basel in December. I found this helpful reading: https://en.wikivoyage.org/wiki/Basel since Basel isn't covered in Rick's Switzerland guidebook.

We will have been in Switzerland for a week then jumping in Rhine river cruise in Basel

Basel has some fantastic museums, if that interests you. One of my favourites that is very unique is the Paper Mill.

https://www.baslerpapiermuehle.ch/en/