Thank you for reaching out to the community forums for some recommendations. I'd be happy to share some of my own insight into these choices to help you find the right fit for your store.
For your theme, the best option is going to vary depending on what you are selling, how big your catalogue is and who your market is. That being said, I can share some of my personal favorites with you to look at:
Dawn Theme - Default - Dawn is our free theme developed by Shopify that runs the new 2.0 theme framework. It is a great starting point for any business and showcases all the new benefits of the 2.0 theme.
Streamline Theme - Core - I highly recommend the Streamline theme, it is very popular with a lot of our merchants. It comes with a very robust set of marketing and advertising tools built right in, meaning you won't need a lot of apps to get those additional features.
Testament Theme - Genesis - Is a great option for stores that sell in person and online. Designed for retailers of all sizes and a lot of merchandising tools.
Startup Theme - Tech - The startup theme is a great choice for companies that sell a small amount of items, or even just a single item. Allowing you to keep the focus on funneling your customers to the checkout organically.
In regards to the Shoptimized theme, I am not directly familiar with it. I will note though that the theme promotes and utilizes misleading marketing tactics to create a false sense of urgency. This goes against the Shopify terms of service and acceptable use policy, which is most likely why it is not part of our direct theme store. Please be aware that utilizing fake urgency tools that mislead customers is not supported on Shopify and could lead to legal action. This doesn't mean you can't use the Shoptimized theme, you just should not use those specific tactics in a misleading way.
For your email marketing, many of our merchants opt to use one of these 3 email marketing tools. All of them are great options, provide very similar features and scaled pricing. I would take a look at their pricing models to see which one is best suited to your business now and what your projected scaling will be in the future as well:
For Mailchimp, if you already have an account setup with them there are apps in the app store that allow you to integrate with your Mailchimp services. Since there is no direct supported connection, most of our merchants opt for an integrated email service if they do not have an existing Mailchimp account already.
I hope these recommendations help you in your decision making!
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