I have seen ECSC used within a framework, though don't know how successful it has been.
I would suggest that the question of inflation should be within the Framework Information, as it is the framework that is to last several years.
Individual work packages within the framework may be relatively small and simple, in which case the ECSC may well be appropriate. Small and simple packages are also likely to be completed within a relatively short timescale and therefore do not need an inflation clause.
Also bear in mind that the framework could be separated into lots, with different forms of contract being available for work packages with differing degrees of complexity.