If your main domain ranks very well, and your blog on a separate domain and separate IP ranks well (presuming the blog has link juice of it's own), here's what I would consider:
1. How competitive is the niche you are trying to rank ? I am presuming it's finance based of your profile.
2. If you created 2 articles, similar topics and posted 1 on the blog and 1 on the website, which would rank better and why.
If the page on your site outranks your blog page, for same/similar keywords, you should consider merging the blog into your main website and do 301 redirects from the blog to your new URL.
EG:
RewriteRule (.*) http://www.newdomain.com/blog/$1
I hope this helps.