Business Writing - Useful tips for email and letters

Form is much more important than content.

Don't worry, I'm not going crazy but the above sentence in a work environment, is a kind of unwritten law talking about email and letters.

Receiving a kind and well structured communication, helps the receiver welcoming and reading it with the right mood. So, how should we set an email correctly?

STARTING (well Begun is half done!!)
Dear Sir or Madam
Dear Mr / Mrs / Ms / Miss Brown
Hi (Informal)
Hello (informal)

GIVING A REASON FOR WRITING
I am writing regard to
Just a quick email to ask
I'm Writing in Behalf of

SENDING AN ATTACHMENT
I am attaching/enclosing
Please find attached/enclosed

INTRODUCING GOOD NEWS
I am delighted to
Fortunately / Luckily

INTRODUCING BAD NEWS
We regret to inform you
I'm afraid that
Unfortunately / Sadly

THANKING
(Always Thank your receiver, He/she is taking some time to read your message!
Being polite is very helpful to get quicker responses too!)
I would like to thank you for
I appreciate your assistance 

APOLOGISING 
(Don't be afraid to say sorry if you have to, we all Live and learn!)
My apologies / sorry / I'm sorry that
Please accept my apology 
I sincerely regret

REFERRING TO FUTURE CONTACT
I look forward to hearing from you
We look forward to working with you in the future
See you soon

ENDING
Your faithfully (if you used Dear Sir or Madam at the beginning)
Your Sincerely (if you used Dear Mr / Mrs / Ms / Miss at the beginning)
Best regards / Kind Regards / Warm Regards
All the best (Informal)
Bye for now (informal)

Let's cut the mustard!