Consider the volume of organic traffic you can get by writing within a specific topic group. Another benefit of the Surfer content planner is that it takes into account search intent, which will help you choose the most relevant cluster according to your niche. Yes, Surfer SEO is very useful for creating SEO content and updating the content of existing pages. We religiously use Surfer on DemandSage, followed by popular SEO tools like Semrush (review).
Surfer SEO has shared a public roadmap with its users on Trello, where you can see what is currently under development and what Surfer SEO's future plans are. Yes, Surfer SEO has recently introduced a free plan that helps you use Surfer SEO for FREE with limited features. Yes, Surfer also provides a reliable keyword extension for Surfer that you can install in your Chrome browser. But for a fair review of Surfer's SEO, I'll say that I've started seeing these kinds of bad suggestions less and less on Surfer.
As for keywords, Keyword Surfer is another part of the Surfer package that is more than valuable. Another free tool included as part of Surfer is the AI schema generator that allows you to generate complete content schemas for your pieces. Surfer also integrates with Writesonic, an AI writing tool that helps create content for blogs and social networks.