I have no opinion because I don’t use space. 
I’m here only because @jan asked me to upgrade space to use SWI-cpp2.h so that it would compile for making a Docker image.
I notice that there’s fairly minimal testing in space/test/test_space.pl despite a fair bit of code (over 4000 lines), and the test mainly (only?) checks space_nearest/4 (demo_space.pl also seems to only exercises space_nearest/4). So, I would vote for a minimal wrapper that doesn’t need much testing. (Yes, I’m a big fan of testing, probably because I so often make mistakes.)
Note that in addition to the 4000+ lines of C++, there are another 3400 lines of Prolog.
Does the C wrapper for spatialindex support something like space_nearest/4? Or does that require libgeos?
If the objective is to get a Docker image that builds, you will probably have problems with space as it currently exists, because space appears to build only with a fairly small set of releases of libgeos++-dev (libspatialindex-dev doesn’t appear to be a problem). So, for the Docker images, I see two options: remove space from the image, or include libgeos as a submodule and build it statically as part of the install process (this appears to be not difficult, but I’ve wrong about such things before).