SEO is not one-size-fits-all.
Although at Fuel Interactive for SEO, we have

…we don't treat every client the same.
We start by looking strategically at rankings, traffic, pagerank, inbound links, and best practice optimizations:
When we've met a client's initial goals, we need to raise the bar. We look for results that are meaningful to the client. Then we say, "Ok, what's next?" We push for the next strategy to get more results.
Targeting Keywords According to Difficulty

There's no more obvious place for goal retargeting in SEO than keywords. Every SEO knows that some keywords are more competitive than others.
Targeting Keywords According to Results
Another way to look at keywords is according to rankings, traffic, conversions, and conversion rate. Here's how our keyword evaluation process goes over time:

Revising Keyword Goals After Implementing Basic Best Practices
One of our clients ranked about #5 for their brand names, and nowhere in the top 50 for more general keywords. Not surprisingly, they required significant best practice optimizations including:
We did all of the above with sensible category-specific and geolocation-specific keywords. The result, after several months, was that the brand name keywords all rank #1, and the site began to rank between pages two and four for more competitive general keywords. We have now switched our strategy to target 5-10 of these more competitive keywords and are building content and finding links to achieve higher rankings for them.
Expanding Focus to Mid-Tail Good-Converting Keywords
Another client was very focused on ranking higher for a very competitive keyword. We had suggested a more broad focus that would start with long and middle tail keywords and work up to the major keyword, but the client insisted. Over several months, we were able to move them from #4 to #2 for that keyword. But we continued to present the data to them, which showed the following:

There's really no disputing the value of their number one keyword, but the next five biggest converting keywords receive more conversions than the main one does. As you go further into the mid and long-tail, conversion rates go up, and ranking difficulty goes down. It makes sense to go after all of these, too one degree or another.
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