Back burner issue:

At the moment,

obs_kind_mod.f90 
obs_def_mod.f90

are created in

assimilation_code/modules/observations/
observations/forward_operators/

Having local obs_kind_mod.f90 and obs_def_mod.f90 created in the work directory would let you compile multiple models/multiple converters at once.

Is this important for users? No not really. Maybe for debugging coupled models if the different models have different obs_def files and/or different quantity files.

It would let you run all quickbuild.csh scripts simultaneously which would speed up testing.
Note you could find&replace in path_names and input_nml to run quickbuild.csh simultaneously for testing.