Hi Salman,
maybe you should take a look at Tag Meta Quick guide available in the download section. It is not update to version 1.3 but the way Tag Meta works is the same.
With my extension you can "overrides" meta info for any url, just leave blank what you don't need and set all the other fields. But Tag Meta is URL-based. I mean, you need to specify for which URL you need to apply the meta info. For your example you could create items as follow:
1) site:
www.systemoflife.com/ it has global meta tags
URI: ^/$
2) section:
www.systemoflife.com/articles
URI: ^/articles$
3) category:
www.systemoflife.com/articles/refutation many categories like this are present
URI: ^/articles/refutation$
4) article:
www.systemoflife.com/articles/refutation/168-shaykh-ul-islam-ibne-tamiyah-ra
URI: ^/articles/refutation/168-shaykh-ul-islam-ibne-tamiyah-ra$
Also, Tag Meta supports regular expressions, so you can specify more than a single matching URL with just item.
This is the reason I suggest to take a look at the guide. As stated on JED description, Tag Meta is not for dummies but is not so difficult, and is very very powerful.
If you need help to set items for your site, let me know,
Luigi