Thank you for your feedback.
1. You can unlock the saved mission and edit it and then save it as a new mission. The missions get synced between accounts and devices so changing it on one risks it all getting unsynchronized. You can delete the old mission right in the app. Swipe left. We don't think it is too onerous and it provides the maximum data safety and flexibility.
2. Stuff like this does come up occasionally. It is a slippery slope though. What about exposure time? What about aperture? What about focus value? What about flight speed? All of these affect the end product as well but are not something that is being saved in the mission plan. We pretty much draw the line at the camera. The mission plan handles the flying and anything camera related is a runtime option.