I (male) have a very good (female) friend over in the south-western United States that I met one year ago and we're exchanging mails or messages from time to time. We're both not older than 22 and I consider her a very open person.
What would you suggest to end the mails with? It shouldn't sound too stiff, but also not too intimate. I definitely don't want to send "Kind regards", but also no "kisses".
In addition, I'd like to know if "cheers" is possible with US-American people?