It will be great to have links in StackExchange Style.
It means instead of having:
It will use:
[MySearchEngine] : http://bing.com
The nice thing about it is if the same link is used more than once in the file it will use the same reference. Also in many cases it will cleaner
This is within the MarkDown specifications, so no need for special extension.
Ctrl+K should prefer this style. If not, at least let user the choice of the two.
Moreover, just like StackExcgange, it will be great to automatically update the numbers based on the appearance order on the page.
It should run on any new added link or by demand.