Could you please clarify, are Monte Carlo (MC) and other non-MD methods of any use within the ESPResSo? I understand that something like GHMC is OK because the same MD VV integration loop is using and all the peculiarities are inside the special thermostat.
So, the main question here: is something like a pure Monte Carlo of interest for further ESPResSo development? If I correctly understand the subject then the MC will have nothing with the real particle dynamics. It is a tool to find some (meta)stable equilibria/equilibrium of the soft matter.
pros: extra capabilities to compare and to validate scientific correctness of the MD/LD/BD within the same framework and same setup. Even for tests, it could be important, probably.
cons: integrate.cpp will not be a focal point of the framework anymore. Get rid of the focus on the particle dynamics in general.
Also, maybe someone could refer me to some open-source project with the well-established MC implementation for the coarse-grained soft matter research? I've tried to find, will look in more details further..