I don't mind late dinners at WDW. Generally we are on a different schedule and will not eat at our "normal" times. We generally go to the resort during the day after rope drops, than venture back out....so it throws schedules off. I will say that 9:55pm might be tipping the scales for me. If it was at 9pm, that wouldn't be so bad....10 pm just isn't a very good time IMO.
I am not sure you will still have bus service back to the resorts from MK. They will continue to run transportation, but it may be a convoluted way to get home (like through DTD or a park with EMH). You can always try showing up early for the reservation and see if you get seated...we have been hit or miss on this.