1. Are cummerbuns mandatory?
Yes, it's part of the uniform, unless you are authorized a waistcoat
2. For air force, do we have to have the tartan stuff or can we stick to black (e.g. black bow tie instead of tartan, black cummerbun instead of tartan)?
You can wear the appropriate branch cummerbund or the tartan one (BTW, black is the branch colour for Naval Operations, so you might not want that one). Bowtie should be black - at least at the start of the evening.
3. Are handkerchief's mandatory?
No
4. Satin or poly type bowtie?
Silk of course
5. Metal clips or full wrap around bowtie?
Proper officers hand tie their bowties
6. Suspenders or belt?
There are no belt loops, suspenders are required, unless you want to be the subject of discussion the next day.
7. What kind of shirt? There's three types: white ruffled with black pin-type buttons, plain white dress shirt with black pin-type buttons, or plain white dress shirt with clear buttons.
No ruffles. Discreet front with tiny pleats is best. The black plastic "buttons" are actually studs, which should be replaced with nicer ones.
8. Or is everything just a manner of preference?
There is some room for preferences, but there is a basic standard.
9. Is there a "standard" mess dress for air force?
Yes, the midnight blue mess kit detailed in the Air Force section of the Dress Manual.