Assume that an incrementing id is assigned to blog posts. The first page would always have the 10 most recent items. The "next" link would look like "/blog?offset=500". So when you click that, you get the items numbered 500-491, and the "next" link on that page is "/blog?offset=490". Admittedly the URLs are ugly, but the advantage is that the contents don't change when items are added, only when they are deleted (the same can't be said for the page=N scheme).
In this scenario up to 9 items on second page may overlap with items on the first page, right?
That would be confusing to users.
Besides, I still see no business advantage of making content hardwired to certain page. If anything, it's better to change page content from SEO perspective.
So the number of items on the most popular page (root) would fluctuate a lot.
I don't think that would make my users happy.
I don't understand your other option. Are you suggesting not to show 0...9 most recently posted items on the first page?