15 years ago, life was simple. There was a small handful of ranking ingredients and it was very easy to isolate them and figure out just what the search engines wanted.
Now everything is interconnected and much more complicated. You need to realize that SEO is less about search engines and more about smart internet marketing. SEO, PPC, Direct Traffic, Email, Branding, etc. are all related and impact each other.
If you have panda, penguin or any ranking problems, I do feel your pain and understand from my own personal experience just how much it sucks. The best way to fix the problem is to be productive and work on the core issues and not just the symptoms.
Here are some examples:
Having Penguin problems?
You might think it is only about your links, you might be wrong. Your content probably also has problems. Huh? If your content was crazy good and had so much value found nowhere else then you would have attracted more quality backlinks and had a much smaller chance of penguin problems.
Having Panda problems?
You might think it is only about your content writing, you might be wrong. Your user engagement & keyword research probably also have problems. If you had better keyword research you wouldn't have just written one anemic page for your keyword. You would have seen the bigger potential to create an entire section of robust content to fully explore the keyword and its many long term opportunities to better engage the user and avoid short stays and high bounce rates. Making your website more valuable and attractive to users would have helped you decrease the chances of panda problems.
By combining all the tools available to you in a holistic marketing strategy, you can create a powerful synergy to lift your website out of ranking purgatory.
Use or start and email newsletter to create strong usage signals for your website and to open up communication with your users to know what content to create.
Use PPC to discover new keywords for your organic SEO content writers.
Have your organic SEO content writers tell your PPC manager about temporary traffic opportunities that they don't have enough lead time to rank organically.
Consider an offline branding campaign to increase direct traffic and help usage signals. Worst case you will make yourself less dependent on Google.
Have your link builder talk to your organic SEO writers to create new pages designed to open up partnerships with other relevant websites and develop links that will actually generate converting traffic.
IMHO SEO is less about search engines and more about smart internet marketing.