Ben Maughan over at Pragmatic Emacs has a followup to his great post on mu4e and Org-mode. Since he recently moved from Thunderbird to mu4e, there are still a few gaps in his email workflow. One of those is the Thunderbird quicktext functionality that provides templates for common email message types.
Following Bin Chen's excellent examples, he implemented his templates with yasnippet. There are a couple of lessons here. First, of course, is that if you are missing some functionality that you're used to from a program you're no longer using, it's usually pretty easy—trivial even—to implement it in Emacs. Yet another reason for moving as many tasks as possible to Emacs.
Second is the power of yasnippet. Whatever you're doing in Emacs, you can almost certainly do it more easily with yasnippet. As Maughan demonstrates (really, just hints at) they are much more than static templates and can be programmed for a rich set of behaviors. If you're not already using them, you should definitely check them out.