I'd like to see a File->Reload Models option that would just reload all the models which have changed since they were first loaded. This would really help in the "fit tweaking" workflow, which is currently:
do { load models; position models; print; test fit; tweak one or more models & regenerate stl; remove all models; } until all good.
With this option it would be:
load models; position models; do { print; test fit; tweak one or more models & regenerate stl; File->Reload Models; } until all good.