Export selected clip
Im aware of the selected range in + out > export selected range option but a related feature to speed up workflow would be to simply > export selected clip.
This saves having to mark sections for export where clips have been manually split. For example, intro's and outros'.
Thanks for explaining why you think selected clip would be a good addition.
Do fill out the ScreenFlow Feature Request Form as well so we can send you a case number and contact you directly about this if needed.