We prefer and suggest Long Tail Pro to all our clients. Long Tail Pro is the best long tail keyword research software online. I use their software for researching keywords for everything from social media marketing bios, to page and blog post titles, to headings (H2, H3, etc.), to meta descriptions, to YouTube descriptions, to content/articles, and so much more!
The Display Planner tool replaced the YouTube Keyword Tool in 2014, and can be accessed from the Tools section of your Google Ads account. Although it's a little more involved than entering a keyword into the YouTube Keyword Tool, the Display Planner offers some great functionality for making the most of Display campaigns, including keyword-driven video ad campaigns on YouTube. The Display Planner also offers precious insights into the demographics and interests of your audiences, allowing you to create highly tailored Display campaigns.
Keyword everywhere is another useful keyword tool. You can install it on either Firefox or Google Chrome. The tool will be able to show you competition data, cost per click, and Google Keyword search volume of multiple websites and keywords. This free extension can help you to save a lot of time. It can assist you to find long-tail phrases including their precise search volume, competition data, and CPC.
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).