I am having a similar problem with /page/2/ and /page/3/ etc not updating their page cache files. The homepage updates every minute just fine.
I have followed your advice to set a low expires time on HTML (currently at 180s). Garbage collection is set to run every 600s, and I even have the Cache Preload set to run every 3600s, referencing our sitemap.xml (which doesn't have /page/2/ etc listed of course). Nothing seems to work.
I've set a cronjob to run wp-cron every 15min (which was happening before even installing W3 Total Cache).
Is there anything else I can do to insure /page/2/ and /page/3/ update frequently? Or something specific to look for in determining why /page/2/ isn't updating in pgcache?
Ideally the homepage and all /page/ files would update automatically every time a new post is entered. My client currently posts 10-20 times a day, and the /page/2/ cache doesn't update until I manually force it to.