Sudden site drop google, not banned or penalised?

[jkossel]

Hi all,

We've been working on our site weldingmart.com for a while. 4 weeks ago we got a sudden drop from google rankings even with our own brand name. No clear cause found, and decided to walk through all technicalities of the SEO fundament. thus we did the following
-> Setup google webmasters tools
no issues found, a few 404's, few 410's sure thats all ok, 
-> Setup robots.txt to only index homepages, lister pages, content and product detail pages (disabled all filters and search queries) Also we banned russian and spammy bots for performance-sake. 
-> Added sitemaps, and around 14k pages seemed to be already indexed. 
-> When searching for "site:weldingmart.com" i can find 14k pages.
-> we had a low 33/100 page speed score and improved this to 76/100

So we did a lot of clean up and improved a lot of items. but still 2-weeks in. we still have no ranking improvements. Before we went down we had around 100 clicks a day from google. now 5 avg.

by the way i think a main issue is the low link count of course but still googling your own name should return us in top3 right.

Is there something we are missing, do we need more time. I just want to verify that we do not mis anything!

[jkossel]

of course we checked that but nothing special, we released a new site in October.

[Igor.Go]

Can you tell a bit more about your improvements? What did you do before the drop?