Branding element across all platforms online and offline

We are a new brand that is currently in the process of a redesign. We used to do trading but now, we will be creating our own brand and products. We will be manufacturing lifestyle bags, primarily backpacks that are retro classic in look and design. Have a look at our current website at [login to view URL] We want to create a consistent look and brand feel across all platforms - website logo, price and branding tag look and feel that are attached at the products, a template email newsletter design, business card and a template offline advertising design for flyers etc. Basically a standard vibe that we can implement across all channels, online and offline. We wish to work with someone that understands the psychological side of branding preferably (how colours affects consumers etc.) Experiences with 3rd party Saas like mailchimp and shopify would be great.