First, find a new printing company that will take PDFs. The images at 300KB are compressed images. When placed into AI the images are uncompressed to their full size. Try opening one of the images in Photoshop and note the size in the lower left. That the size AI sees. The best bet is to deliver PDF files which can contain compressed image files and live text which will print clearly.
Thanks Larry, I figured out how to compress the images once in Ai, but it would be helpful if I can get the answer to my other question #1. How do I keep text crisp while saving in jpg? Switching printing companies is not an option for many reasons. One of which, its an photography album company, they do great work and are the best I've found after many years of research. 2nd, I never have text in any of my previous albums, just the one I'm doing this one and only time. I don't want to switch companies for just one album...
How do I keep text crisp while saving in jpg?
You don't. JPEG is strictly a raster image format. It cannot contain live text objects or vector-based paths (which is what you have when you convert text to outlines).