Welcome to the Q&A Forum

Okay, I thought I was following best practices.  In our industry, electronic hardware, we were ranking well for a particular product line (/spacers) but we wanted to do better.  We addressed several concerns that Moz found first; duplicate page titles, lack of meta-descriptions and overall lack of targeted keywords.  We also took a new approach to add a better structure to our site.  Instead of being presented with a list of part numbers we wanted the user to learn more about our products with content.  So we added a /products page with content and a product specific page (/spacers) that is almost a definitive buyers guide. We are attempting to answer the questions that we think our customers find most relevant.  Well our customers might find it relevant but Google sure didn't.  After our deployment of new content our rankings for targeted keywords in Google fell from  10-15 to 80-95 As an open ended question, could somebody explain to me why our ranks fell off a cliff? Homepage: https://www.lyntron.com
New catalog summary page:  https://www.lyntron.com/products
New content with focus to rank high:  https://www.lyntron.com/spacers TPdn6ym

We are a electronic hardware manufacture with a fairly large catalog of products.  I dynamically built our site and we have over 705,000 unique products that we can offer.  With our php framework I was able to create sitemaps that hold every product unique url.  After doing all of that I submitted our data to Google. Then waited with a cocktail encouraged that we'd grow up the ranks of Google organically.  Well, that didn't happen. Besides several other problems (lack of overall unique content, appearance of duplicate content, no meta description, no unique page titles, poor use of heading tags and no rel canonical tags) how can I get a "do-over" with Google and my submitted sitemaps?  Can they be re-submitted?  Can they even be deleted?