Add more emojis to picker

Hi

I read a lot of marketing materials that say using an Emoji in the Subject Line has a better open rate.  

I wanted to know if there was a way to add a company logo to the Subject Line of outgoing emails or if there was a way to create an Emoji from a Company Logo and add it to the existing listing of Emojis available?

Personalizing an email is great but adding a Company Logo will identify the email as not being junk mail when spotted in someone's email listing.

As an insurance company, any other existing Emoji would not work for a professional organization.

Any ideas on how to create this would be appreciated.

Thanks