Another reason for putting it off is that I still haven't figured out a sane approach

to handling arbitrary fonts in a diagram where everything is absolutely positioned. 

In fact I only have a minimally-workable approach to handling a single, mono-

spaced font across platforms.  For example, there was a change somewhere in

the Gnu/Linux font-stack (relatively) recently that renders fonts (or at least

DejaVu Sans Mono) noticeably wider than before.  So Windows, OSX, and

old Gnu/Linux would render a particular line of text sized at "12px" within less

than a single pixel of each other.  The new Gnu/Linux font stack (seen in Ubuntu

16.04 and some recent Arch) rendered the same text about 7 pixels wider.

Worse, the newer Gnu/Linux font stack quantizes the "px" sizes such that the

next smallest size is noticeably smaller.  So in Ubuntu 16.04 I have to compromise

by keeping the object box the same size and having some extra padding at the

end-- otherwise users of that OS could end up tightly spacing their object chains

in ways that cause overlaps on the other platforms.

So... I'd like to get a handle on that mess first, then handling arbitrary font

families-- as in cyclone/comment-- will hopefully be easier and less prone

to bugs.