A website with good SEO friendly but lacks in design features will not be engaging for the users. I think both factors are equally important and go hand-in-hand. An attractive website will make the visitor or user explore other areas of the website. Therefore, a well-balanced structure would be ideal.
Good design is very important as well as the content. Users will read your whole content if the design would attract them otherwise there is a chance of bounce rate so meta tag, meta description, and meta title are best to escape from this bounce rate and user stay for a long time.