I also start each on a new line to accommodate as many email clients as possible. A quick proofread can catch most syntax problems. Having said that, I recognize that email is less formal than most traditional business writing. Personally, I'm quite tolerant of surface errors as long as I understand what's being said. This is a little snippet of text which the email client will automatically include at the end of every email.
Many people also add a pithy quotation like the cartoon they'd tape to their office door.
As with my other choices, I wanted one phrase or word that would not be perfect for every occasion but would be acceptable for all occasions. Sincerely seemed too insincere and frequently false. Best and regards seemed OK but bland. To balance hi , I could use bye , but that seemed too cute. Omitting it altogether and putting only my name seemed too abrupt.