Digital Marketing support

I need marketing support for my sports nutrition business. I sell through my own site, Amazon and eBay, as well as to some businesses. I want to drive more sales through my website. Nothing unusual there.

What I am doing:
1. Social media. I have FB and Instagram for the business which is ok, but could be much better.
2. Google ppc - this is driving some traffic to the site

What I am not doing:
1.Email marketing. Yes I know, that's a huge thing to miss out! I want it to be done right, and I do have a list of a few thousand people who have bought from my company. I'd definitely like this to be set up and managed
2. SEO.

I realise digital marketing can cover many different areas, so what I need is someone to review what is being done and what could be done better, but definitely this would include setting up email marketing and some social media work. Hopefully this would be on-going, as I'd like someone regularly involved with my business, who understands it and can be proactive in helping me to grow it.

Thanks
Drew