Keyword Researcher is designed to search the Autocomplete databases of Google, YouTube, and even That's a lot of keyword sources! As you probably know, if you're building an authority site, or if you would like to become a dominant player in your niche, then starting with a large database of keywords (that your customers are actually typing in) is a powerful marketing tool.

Am I worried that my keyword research might not be effective since I only look at the KC score? No. Not really. Because I tend to target only the longer tail keywords these days. I don’t go after the huge main keywords anymore. They’re too hard to rank for. But long tail keywords are really easy to find with Long Tail Pro and they are usually much easier to rank for.
This makes Google Suggest a relevant source for keyword research, it contains a large amount of organic keywords very closely related to a full or partial keyword and can be used to find additional most searched appending keywords that make the whole keyword less competitive. Google Suggest can be researched through the Google Search website or through a compatible browser for a small amount of keywords but also in large scale using free scraper tools.
Long Tail Pro by Spencer Haws is the most useful keyword research tool that you can use for your internet marketing. Thousands of webmasters depend on the tool to generate thousands of keywords. It is such effective that it has dominated the keyword search market for the few years it has been into existence. It would cost you less than one hundred dollars to have access to this important life-changing tool.
To get started with the Free Keyword Tool, just enter a keyword or search term into the relevant field. If you want to conduct competitive intelligence research into your competitors' keyword data, you can also enter the URL of a specific webpage to view keyword data for that page. You can also enter your industry and country to see even more accurate results; it's not unusual for the cost-per-click and other metrics to differ widely from one country to another, even for advertisers bidding on the same keywords in the same industry. 
3. Set your pre-search filters. Depending on whether you are looking for a new niche to build a site around or trying to find keywords to target on your already existing website, the minimum amount of local monthly searches (LMS) you set might vary. For new niches my LMS criteria is 1,500-5,000 searches, for posts anything from 10-800 is fine. Also, depending on one of these goals you can add a lower or higher number of words in the respective filter: for new niches 3 (or, at times, 2) words minimum, for new posts from 3 or 4 words up.
Spencer, it seems like you got out at just the right time and made your money? Seeing as Google has basically stopped giving access to their free keyword tool. I own the FULL lifetime license $290+ I think is was. Now Longtail Pro is useless due to the restrictions that Google has put in place. Do you know what the future plans are for Longtail Pro to get around this issue that I’m sure everyone is facing? Or can you get some feedback from the new owners?
One possible problem is that although the Keyword Planner has some cool new features (including integration of the Google Traffic Estimator, which will be retired too), as of this writing, the indispensable Exact Match and Phrase Match features are nowhere to be found! Whole books will become useless without these, so I hope Google will eventually port them to the Keyword Planner. Nor do you see the “Include specific content” option, which is a life-saver for the adult industry, which spends the most on Google PPC.

He is the co-founder of Neil Patel Digital. The Wall Street Journal calls him a top influencer on the web, Forbes says he is one of the top 10 marketers, and Entrepreneur Magazine says he created one of the 100 most brilliant companies. Neil is a New York Times bestselling author and was recognized as a top 100 entrepreneur under the age of 30 by President Obama and a top 100 entrepreneur under the age of 35 by the United Nations.

The limit on manual keywords could be higher.  I personally wish we could input 10,000 keywords at a time, instead of 200.  However, I understand the costs that Long Tail Pro has to maintain each time a new manual keyword is input.  Not a deal breaker, I just wish the limit was higher. (To be fair, I don't think most keyword tools have a bulk manual option at all).