I've got 1/1-8 tires on it now, and the spouse has 1 inch, so I reckon 1-3/8 will make a difference. And as you say, there's not much choice. I had not thought of low pressure being an advantage, but of course it is. Silly me.

The other option is to rent a hybrid, but what do I have the Friday for if I end up doing that? I love that bike. I want to give it a chance to shine off road as well as on.