I quite like the portrait.
To me there are three elements to this picture: the setting in the room, the sky outside, and the face.
To me, the room signifies tradition and a long constant history, an institution that has been running for a *very* long time. As an institution, it's seen all that can happen and yet still continues (whether it should is another question of course).
The sky outside signifies the gathering clouds with rays of sun trying to break through - what is going on outside? We're not sure because we can only see a glimpse; but either way, it's changeable and uncertain from our PoV. But the face is looking out and seeing all out there.
And the face is calm, maybe faintly amused by the "same old" storm that will end everything ("yet again!") happening outside, but not with resignation: more with curiosity, and deeper than that, a satisfaction that some things will continue. Almost like the face realises that the storms will continue to rage just as the room will stay exactly the same as the years pass by, even if the face will change.
Maybe she's laughing that she could impress her personality so little upon things: she almost looks like she still feels like a young girl put into a mad world and asked to do the impossible; and after doing it, still wondering how she managed.
But then, maybe she's this person stuck in a dead room in fine clothes waiting for a royal portrait when she would rather be outside playing and having fun whatever the weather when she has other responsibilities to meet?
I can relate to this picture even though I'm British and a republican. It shows a wonderful depth to a human being stuck in very strange circumstances.