Please, change the default export setting to export 'Source in/out' and not 'entire source'

That sounds like the logical behavior I'd expect for standard export 

Have you considered using Quick Export? If you have an in/out point set Quick Export will only export in/out, whereas if there's no points set, it will export the entire source. 

As far as I can tell, the export tab remembers the last source range setting used.

I understand but it might be confusing to other users who expect the whole source to be output.