Having concinnity, which noun form is slightly older in English: both were borrowed from Latin, this from concinnus, neatly arranged, around 1650, while the noun from concinnitās, a nominalized form of the same word, around 1530. I assume the con- part of the Latin is the usual prefix meaning "with," but I cannot confirm that at this time. A tightly structured novel, with no lose plot threads, where the language matches the tone and theme is concinnous. It seems fitting to use a translation of Cicero (from Brutus) for an example use:
"But there are likewise certain forms of expression, which are naturally concinnous, as will necessarily have a similar effect to that of regular numbers."