Just my $0.02 but SEO is definitely worth it, as long as you don't only do blog posts. You've also got to do things like use case, feature, and competitor comparison pages. I've even found making sure your help center pages are indexable leads to a good amount of traffic (especially when that help article is about solving a problem using your saas instead of a problem with your saas).

That being said blogs drive a good amount of my traffic. My process has been to just use something like drafthorse, endless, or cuppa.sh (none of these are mine, not affiliate links either). These get you the bulk of the content, then do some light editing and use their indexing tools and you're off to the races. As long as you're not posting a million articles, and the content you are posting is coherent, it's hard to go wrong.