Christina,
You are missing the point. Each time you fiddle with the site you think you are improving things. In reality you just make it worse. Go back to basics a decide what you want the site to acheive and build from that. The site has totally lost its way. Don't touch the theme until you have done a lot more research.
Firstly,
Blog commenting is not at all a good back link strategy.
Many blog commenting systems in today's day and age operate a "no follow" tag, as blog commenting was heavily abused by spammers, using it to gain nothing but back links.
Unless your goal is to gain advice or direction or communicate with the author regarding the article, blog commenting is not a productive way to try and gain back links in today's day and age.
In regards to your site,
you need to far less focused on off page SEO,
and understand and implement correct on page SEO.
Focusing on nothing but the search engines and back links,
you've missed many vital aspects of a user friendly site.
There's a couple of free tools that will guide you in how well your site is rendered,
but again this is in the eyes of a search engine which don't get me wrong is important.
I'm not going to add them as this again should not be your area of focus with the site as its stands.
You need to make the site user friendly first
Don't try and run before you can walk. Look at the time wasted already.
Get back to basics as advised,
start with a more suitable theme, and focus each page on a topic, then conduct correct keyword research. Following on from that you need to create quality, unique content that's SEO keyword written along with a user friendly site linking structure that's easy to follow.
There's no point continuing and adding to the site.
It would be far easier for you to take a step back and start again,
focusing heavily on a good theme, keyword research, quality targeted content as per newly assessed and converting keywords and implement good site structure.
In doing that and keeping your users in mind,
you will also fair well in the eyes of the search engines.