New site, many new problem, many more questions... HELP!

So in mid december we launched a brand new website that had been around for ~20 years
the site was built on a .asp server and we switched to a linux based server
needless to say all of out link structures changed from ending with .asp to ending normally
The content got better, the code got better and the structure got better
basically everything improved..... but we are losing rank like a sniper shot us in the leg while running a race
we did a 303 redirect on some of the most popular links and daily add more relevant content
any suggestions on where to start looking? www.amberusa.com is the site
you can check out the old on archive.org if you want
I also want to know how to best use our blog we have a blog on the site that we write 2 original post from per month
are we getting the proper juice out of it just by it being on our domain and linking to relevant places on the site or is there something we are missing

thanks in advance

Justin

is it your redesigned site, i request you to have a look at modern niche specific ecommernce site.your site design looks pretty old, and structure also seems little messy.

Redirect the links that are backlinking to the .asp URLs to the new URLs. Run them through an indexer after you do that. Make sure your on-site SEO is reflective of your keywords, and start building new backlinks to your main site and building backlinks to the old backlinks that you are redirecting.