Diachronic Construction Grammar currently faces two challenges that tie to the systemic nature of language organization. On the one hand, schematic constructions characterized by a filler slot (such as the verb in the [be about to {V}] construction) have been associated with a paradoxical observation: an increase in the number of types recruited in the slot of the construction can co-occur with a general decline in frequency of use. On the other hand, constructional changes happen on multiple levels of the constructional network: lower-level constructional schemas (such as the partitive [a piece of]) get entrenched and strengthened as instances of higher-level schemas (e.g. the family of quantifier constructions [(a) {N} of]: a piece of, lots of, etc.), and therefore benefit from a mutual relationship while they compete over the same types. This project aims to tackle these two questions with innovative methods from Complex Systems. To elucidate the first paradox, I rely on the observation that the types of a filler slot obey a local Zipf's law. The hypothesis here is that this Zipf's law gets entrenched as a characteristic feature of the construction; when too many types are recruited, the Zipf's law cannot sustain them all and collapse, leading to the decline of the construction. To solve the second paradox, I will invoke the notion of nestedness, borrowed from Ecology: if a paradigmatic system achieves this property, then competing constructions can successfully coexist.