I definitely feel your frustration. I do most of my writing in DT as a lot of my text is in the form of annotations or references to existing documents. The basic flaw is the lack of development of OS X rtf component but some apps, like Scrivener have hacked the rtf component to add more functionality.
One approach which might make things easier is adding keyboard shortcuts to the styles menu as described in this thread:[url]Script to apply style within RTF *and* Label the RTF].
The other approach I am still going to try, is to use applescript to produce neat multi-level numbered lists which is my particular requirement. I have already had great success in manipulating the text in an rtf document using DT’s applescript ( see here as an example [url]Updating reference links to Bates numbered documents] as well as many other scripts on these forums).
The last approach which might be worth exploring is writing in markdown instead and for which DT has some support (although I wish it had an option to support a markdown engine of one’s own choosing).
Frederiko