hi Guys,
Found this thread and happy I did.
My wife and I started two shops a few months back:
www.matalinoshop.com (viral products,
www.vachementshop.com (jewellery, Ecwid)
We are also creating single product flows which we will be running ourselves, can I post these here aswell?
please shoot as many holes as possible, here to learn 
Cheers from Amsterdam
Nice-looking stores! 
The viral products site looks very promising! I would suggest to add more product information to each product - a LOT more info and sales pitch and testimonials etc. Then run some FB camps to drive traffic. Test 10-20 products in this way to identify products you're able to break-even (or close) with, and build out a site for each. After that, consider buying in bulk from manufacturers and distributing locally to minimize shipping time, which would be a big selling point.
As for the jewellery site, I haven't tried selling jewelry myself, but have heard from so many ecom experts that it's not an easy type of product to make profitable. There are way too many similar sites. If you want to go that way, consider niching down - e.g. spiritual jewelry. See if you could identify certain audiences on facebook you can target before choosing a niche.
Would love to see your single-product flows!
Amy
I browsed your shops for a while and here are some tips for you.
1. About us and FAQ pages have a prominent spot in the menu, but the actual pages are very blunt or empty. Doesn't really add trust.
2. Contact us page on vachement is jsut a simple form, without any details about the company. On matalino, there is no contact option at all. Again, this is not good in terms of gaining the trust of shoppers.
3. The information page on vachement contains some grammer mistakes, not sure how many people are actually reading these, but it might make sense to get someone to proof read this for you.
4. Product images: some are great, but in some cases it's hard to see the details. How about installing a "magnifier" kind of plugin? I've seen this on many shops and it could do well especially with the jewelry products.
5. As Amy mentioned above, I was also missing some more details about many of the products. For example in the "sports/exercise" product category. Maybe even add some videos of the products. More photos wouldn't hurt too.
Anyways, I know this is just the start so there is much to improve and you will get there in time 
Wow guys!
Thank you so much for the tips! We are going to apply them as best as we can

You should create the default
Settings > Legal > Refund, Privacy, Terms
You mention a returns policy in the graphic, are you sure this is something you're willing to honor?