Nah, the problems in the end are only that in the slideshow, you are told about change x and y, but if you continue the game, nothing of this exists. Also none of the npcs will react to you in this way. Adding this additional reactions and other changes would mean lots of work again, which is totally unneeded, in my opinion.
I can't understand as well why people want to continue the game after the end. Just reload short before the finale and do whatever else you want, where is the problem?