First is Google, who we use for company email. This means any interaction with our customer support team has emails stored with Google.
If you self-host everything else, why don't you do the same thing for emails as well?
I can't speak for Foundation, but I do know that - especially with outgoing emails - self-hosting these days is a pretty big challenge.
Some providers will immediately flag your emails or delete them outright due to too strict firewall settings. Imagine a customer not receiving a response because their email provider didn't let Foundation team's reply through. That will probably be the main issue.
Maybe a support thread on Bitcointalk, together with support through DM (even if it may sound silly) could be a better way, avoiding email completely.
Do you have any official reseller stores in US and in other parts of the world that can sell Passport devices for cash or bitcoin in person?
I think this is a best way for reducing digital footprint and there is no risk of any leaks happening in future.
I agree that local and international brick-and-mortar resellers / distributors would be a great idea.
Though up until now everything was preorder - I don't believe that in-person preorders are very convenient; the customer would at least need to visit the store 2x. But then again, they may actually be willing to do it.