I think for agencies as far as how we appear in organic search ourselves, we are definitely going to need to leverage all 3 of the solutions you talk about and agencies who haven't branded their products/services are going to have to do that and are going to have to also employ branding strategies. In addition, we have to optimize for other search ares like you say in your point #2 and we must look at optimizing existing content for voice search and answers/featured snippets like you say in point #3.
Content is one of the 3 main Google ranking factors. As a matter of fact, having a blog can help you get your content indexed faster. An active blog – relying on qualitative and insightful content, and backed by authoritative links – will help you improve your rankings and thus your organic traffic. Also, long-form copies (above 1200 words) tend to rank higher and be crawled more often.

Probably the most well-known Integrated Vertical Search is  Google’s “Universal Search” –  although all of the major search engines have now adopted similar search formats. This is the practice of incorporating different types of results in the Search Engine Results Pages (SERPs), such as news releases, images, videos, etc., depending on the query.  This was a game changer for SEO when it was first introduced – it became necessary to create and optimize many different types of content because they all show up on SERPs. The term for this comprehensive approach is referred to as Digital Asset Optimization (DAO).
Many people know which search results are paid versus natural and often give precedence to natural search options. On the other hand, if your website shows up on later pages of the search results, you might have better luck using PPC to get seen. Because PPC costs money, you might consider using it for items that you sell, as opposed to promoting a free offer or your blog. With that said, many people have successfully used PPC marketing to promote a free lead magnet.
And then if that isn’t enough, what I’ve seen work well is provide some incentives. Have a social contest, a social engagement contest, where people can like content for an opportunity to win say $100 gift certificate, something small scale like that. I myself have been part of these sort of contests before for a number of organizations and see it really amplify the engagement, it gets it in front of your employees’ eyes and thinking about it. And then the beautiful part is after the contest is done, the habit’s built oftentimes. And you’ll notice those same people that were engaging initially for the contest continue to engage with your content and help amplify your message.
Audience insight.  The better you know your customers’ pain points, the more tailored your offers will be. The more you’re connected with how they feel, the more succinct and impactful your messaging will be. I can’t think of one aspect of marketing that isn’t strengthened by that depth of audience research.What does organic traffic have to do with it?  When you dissect your traffic, here’s what happens.
Anyone who types in a search query has a specific intent. And they’re expecting the content that they find in the SERPs to satisfy that intent. If you can understand the search intent of your prospective customers, it will transform your marketing in several ways. You’ll be able to predict what keywords your potential customers are likely to use.  It’s easy to start targeting keywords with no structure or strategy. But that’s a mistake.
Organic is different. Matching keywords to user intent means you may be present in many searches. The user may find you consistently, and once they get to your site, they are more likely to stay. Organic users are still your best long-term customers. In my experience, they have lower bounce rates and more pages visited, and they are more likely to return.