Josiah,
In some ways as soon as an application claims to have custom macros available it advertises flexibility. Just look at other applications in the market, few have custom macros but many promise addins, sometimes these add ins are not very helpful, but they are trying to compete with other solutions that empower the users with custom macros. It is true us TiddlyWiki enthusiasts come to learn this flexibility is enormous and other may miss the value to custom macros.
I suppose what I am saying is without getting into too much TiddlyWiki details promoting the value of custom macros generally then pointing out how well tiddlywiki can implement them may be a good strategy.
An application that includes the ability to build custom macros empowers the users and designers of solutions in that application with almost unlimited possibilities. Custom macros allow the encoding of additional logic, manipulating what is displayed and allows you to build your own algorithms into the application. Custom macros acknowledge your needs may differ from the application designers perceived needs. Effective custom macros can encode logic, manipulate sets, do maths and support interfaces with users, to simplify everyday use. TiddlyWiki's custom macros Exceeds the capabilities of many macro solutions. In addition there is a community behind this and many macros are commonly shared with many also being moved into plugins or add ons.
By promoting the concept of the flexibility of macros generally, then demonstrating the power of TiddlyWiki macros specifically I think we could persuade and compete with other solutions effectively.
Why should we try and persuade people to use tiddlywiki, because every new enthusiast brings new ideas and skills to the community as a whole. A Community I have always treasured, but still in a position to grow and open up further.
Regards
Tony