I am using SEO Ultimate and I cant think of what it cant do.
I just threw it in and tweaked it a bit and wow.. my site was with high seo measures..
I was able to map my tags and categories as keyword meta tags
and map post excerpt to description tag. I could also rewrite titles to include my site name and a couple more things.
I am using a different plugin for XML sitemaps though it is called:
Google XML Sitemaps
I would highly recommend using WP-reCAPTCHA unless you wish to invite thousands of spam comments your way.
I hope this helps :)