The overall plugin looks very decent, however the part of placing (inserting an appropriate keywords) is not. For SEO you should do this manually and by not repeating the keywords all over the place.
Best results are achived:
First paragraph, good/quality content. Never use generators like that, because you will "shoot yourself in the foot" if you let software generate keywords and "stuff" them into content.
I can recommend http://yoast.com/wordpress/seo/ instead and https://adwords.google.com/select/KeywordToolExternal for true keyword research.
I can't stress enough how important is not to have this in any site, not just WordPress.
Also when time allows go over this article as well: