What others are pointing out here is that if you have a project in ICO stage and a good website, it does not look very professional to use a gmail ID. Also it does not help build trust where as it is easy to create a more official email ID now a days to show it is coming from a professional company.

BTW, you may also want to highlight what do you expect from this title partner as I believe everyone may have a different meaning of same.

I looked at your website and also team and project looks very promising.