What would (did?) the remaining living royal members portrayed say if they saw it?
In addition to the thread below, these previous answers might be of interest while you're waiting:
Did Queen Elizabeth and Prince Philip really have such a rocky marriage in the early years of her reign? by /u/PM_ME_YOUR_DALEKS
Also, the Queen actually has watched the show and according to a "royal source" quoted in the Telegraph, "she really liked it, although obviously there were some depictions of events that she found too heavily dramatised."
Only one very specific angle, but I imagine /u/mikedash's answer here will be enjoyable for you!