How to Build High Quality eCommerce Web Site during Low Quality Web Pages?

[CommercePundit]

Today, I was reading Official Google Webmaster Central Blog: More guidance on building high-quality sites.

I found one interesting statement over there.

Low-quality content on some parts of a website can impact the whole site’s rankings.

Why should I like to discuss on this topic? Because, I have made big change on my website via narrow by search.

I want to give specific result to know more about it.

This is my category page: http://www.vistastores.com/patio-umbrellas

Left narrow by search section is creating accurate page for specific attribute products.

California Umbrella:
http://www.vistastores.com/patio-umbrellas/shopby/manufacturer-california-umbrella

From above page following page is accessible.

http://www.vistastores.com/patio-umbrellas/shopby/canopy-shape-search-octagonal/manufacturer-california-umbrella

Sunbrella Patio Umbrellas:
http://www.vistastores.com/patio-umbrellas/shopby/canopy-fabric-search-sunbrella

Similar story for this page. Following page can accessible from above page.

http://www.vistastores.com/patio-umbrellas/shopby/canopy-fabric-search-sunbrella/finish-search-wood

My website have 100+ categories, 11,000 products.

I have checked indexed pages in Google for my website.

https://www.google.com/search?q=info%3Awww.vistastores.com&pws=0&gl=US#hl=en&safe=off&pws=0&gl=US&q=site:www.vistastores.com&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&fp=910893d99351c8f7&biw=1366&bih=547

It shows me 35,000+ crawled pages which are developed by left navigation section.

So, Will it consider as low quality pages? I want to improve my website performance without delete these pages.

[DavidLenehan]

Do some reading on the canonical tag and using it on ecommerce sites.

[CommercePundit]

I don't like to set canonical tag on my eCommerce website. Because, I have already set up canonical tag on my previous version. I want to open my pages for crawling, indexing and ranking.