It really depends on content. You can lower the quality doing a custom production in Camtasia to say 50%.
If your content is nothing more than a screen recording. You didn't use zoom in and zoom out animations. It's a Microsoft WORD tutorial, or perhaps a Excel Tutorial.Things of this nature. Lowering the quality shouldn't hurt the overall quality.
Recording with highly detailed images and videos. Content with a lot of colors. You'll find increasing the quality may be warranted instead. That's just the way it is.
I don't know what video dimensions your working with? If it's 1920 x 1080. You might want to think about switching to 1280 x 720. It will reduce file size dramatically and should leave you plenty of head room to produce at normal to higher quality output levels.