9.10 is too constraining
'''9.10 Software must not encourage lock-in'''
According to the UNIX philosophy and KISS principles, core software in Devuan '''must''' follow the "do one thing and do it well" with the only exception of the OS kernel. Core software included in main distribution '''must try''' avoid to require other independent parts of the system to function, trying to provide best portability, POSIX compliance and standards adherence.
Usage of the word must in this point is confusing. RFC2119 defines keywords to indicate requirement levels, and is an Internet Best Current Practice, which means using such words in the Devuan Constitution will have consequences in the interpretation of its meaning.
I think it SHOULD use "should" in both cases. It's preferable to use software that follows the KISS principle, but some software integrates more than one functionality as it is more complex. For example,
nginxis a Web server, but it also can be an SMTP proxy, which technically is not ''do one thing and do it well''.
The KISS principle of UNIX works well for the Shell but applications are a different beast. For this reason, I suggest relaxing the requirement, and make it perspire everywhere in the documentation and the code that the preferred way is "as simple as possible, but not simpler" (Einstein), instead of a hard "do one thing and do it well".