Amboise or Tours?

You cannot really visit Amboise without visiting the Royal Castle (Clos Lucé is less worth it IMO), the town besides the castle(s) does not have that much to offer.
So, if you are really allergic to castles, I would say Tours is best.

Amboise is a well-preserved medieval town of 13,000.
Tours is a university city of 360,000 with a lot of its medieval structures intact. They’re both similar in the time period they originated but different because Tours is a large city.

It is difficult to make the most of the Loire without a car, and it would requires commercial van tour assistance. There is no point in going to the Loire if you don't visit any Chateaux.

While Tours is a larger city, the Tourangeaux call it "Une ville à la taille humaine" (a city that's easy to traverse and where every neighborhood has what you need). I'd vote for Tours. But I may be biased, because I took some college courses there. It's an excellent base for Loire Valley trips and when you get back from a long day of chateau hopping, there's nothing like going to "Place Plum" or a dinner or Rue Colbert.

We are visiting 2 castles( clos Luce and Chemonceaux, but we want a down day to wander the town. Sounds like Tours is the better place to do so?
We are actually staying in a smaller castle just outside Amboise for 3 days.
Thanks for the replies everyone.

Clos Lucé is in Amboise, and close to the town center, so if you visit Clos Lucé you will visit Amboise whether you want it or not ;). It's a small town...

I haven’t been to Amboise, but I stayed in Tours in 2019 for a few days. I stayed at Hotel L’Adresse near Place Plumereau in the historic center. I walked around the center of town quite a bit.

If you’re open to another option, I loved Angers! It’s an hour by train from Tours. For Angers, I stayed at Hotel Continental which is located behind the Opera House on Place du Ralliement square – a very handy location since the tram from the train station stops at the square. This hotel is a no frills but perfectly adequate hotel. I purchased their breakfast since my train was leaving late morning. A funny discovery was that the L’Arelequin shop that I wanted to photograph ended up being right next door to my hotel!

Angers has a young vibe and Parisian architecture. I really enjoyed walking around town and being at the Place du Ralliment in the evening and could picture it as a possible city if staying for several days.

Amboise for me. I was riding a bicycle through the area. Tours is a city, much not at all attractive, with some nice local sights. Amboise is a really nice little town, with a surprising number of sights locally (and others nearby).

I focused on the western side of Loire, Chinon to Amboise. Best advice was to pick a handful of chateaux and stick with those. If I'd focused on the eastern side of Loire valley, I'd probably have picked a similar base located closer to the chateaux I wanted to visit.

Very helpful. Thanks! We are in a chateau just outside of Amboise. Lovely little town.