Except Outlook 2011 for Mac has the exact same issue.
You have no idea what the email will look like when someone opens it on Outlook on Windows. On your end it looks perfectly fine, the way you formatted it. But on the receiver side, if opened on Windows, it has different fonts all over the place, different font sizes in different parts of the email, a couple of paragraphs will always be huge, irregular spacing, often double or triple spacing in between a couple of sections and parts of the bullet lists.
I get comments from my coworkers and clients that opens my emails on Windows all the time. The emails become almost incromprehensible unless its in plain text with no HTML formatting. Makes me look like a **** fool every time.
I appreciate that you want to let the receiver dictate the formatting in some cases as they may have bad vision etc. but in business when 95% of your recepients just want a standard HTML formatting that they can read without getting extremely frustrated I could care less about the people who wants to dictate all their emails to be in Wingdings 42pt.
Come on, can we not solve this? Email is such an old way of communicating, how do we not have a standard formatting on both sender/receiver end already?