2) SEMrush- This tool offers fantastic competitive research around domains to find what keywords could be driving traffic for your competitors. Looking at paid keywords ad spend can also help you know which keywords might have monetary value worth pursuing organically. If a competitor is willing to spend a high ad budget on terms and you think they do a good job running their ad campaign, then its a good indication it is worth organic ranking effort.
Long Tail Pro is a keyword research tool. Keyword research helps you find exact keywords that people are actually searching for. Some keywords are high competition (meaning it is harder to rank for on your site) and some have lower competition (easier for you to rank). How does Long Tail Pro work? First it finds the actual keywords for you based on the ‘seed keywords’ that you input. Then it helps you analyze the competition to see which keywords will be harder or easier for you to rank. How does this benefit you? You can take those ‘easier to rank’ keywords and use them in your content to increase search engine traffic to your site.
How much is a keyword worth to your website? If you own an online shoe store, do you make more sales from visitors searching for "brown shoes" or "black boots"? The keywords visitors type into search engines are often available to webmasters, and keyword research tools allow us to find this information. However, those tools cannot show us directly how valuable it is to receive traffic from those searches. To understand the value of a keyword, we need to understand our own websites, make some hypotheses, test, and repeat—the classic web marketing formula.
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).