Howdy iHasco!

Big site changes like this can always be tricky. Depending on how often these paginated pages are indexed and how many external links are currently pointing to them (I'd take a look and analyze both of these things before making any concrete decisions). Either of these decisions could be an okay route.

404 ing them is appropriate if the pages arn't indexed in Google, and have no backlinks.  (Be sure to remove all internal links pointing to them as well)

301 redirecting these pages is the correct route if your pages have link equity you want to preserve or the pages are indexed and users could potentially still access them from the SERP.

Since the blog homepage will contain the content these users would potentially be looking to access, I think that the blog homepage is the correct page to redirect to, as it will house the same content as the pagination used to have.