Besides the Machu Picchu Journey, and time at the Amazon, has anyone spent time at beach or done anything else they have found especially memorable? thanks!

I didn't visit the Amazon, and I'm not a beach person. but I did spend a few brief moments at two different beaches in Peru -- La Pimental, near Chiclayo, and Huanchaco, near Trujillo. I visited a number of fascinating ruins, saw some spectacular scenery, savored delicious foods, was fascinated by museums with various artifacts, roamed through lots of colorful markets, and much more. If you haven't already seen it, you might find some ideas in my (very long) trip report:
Praise for Peru – A report of my solo month in this amazing country

Chachapoyas, Huaraz, and Trujillo in the north of the country were especially memorable. Arequipa and the Colca Canyon in the south also spring to mind.

Some details and photos of our time over many visits to that wonderful country are on our blog @ https://accidentalnomads.com/category/peru/

A lot depends on your interests of course, but if into hiking in spectacular mountain scenery, then I highly recommend Huaraz. I don’t really think of Peru as a beach destination, but Mancora is possibly the most popular area for people seeking beach time.

We did a rafting trip and a half day cycling trip out of Cusco with:

Amazonas Explorer- The Cusco & Sacred Valley Adventure Specialists

They were organized with good equipment. That was in 2012.