And it's also why an [elected] upper house would be a completely flippin stupid thing to do
An elected upper house could, possibly, work, but only if they stood for a long time.
My own suggestion would be along the lines of a 15-30 year term, with a third of seats up for grabs every 5-10 years.
Whatever happens, we need someone to look at the long term. In fact, this is where the Queen (should) come in. She shouldn't be blocking legislation. However, should something go through which was utterly insane, I believe she would (should) still be able to refuse to sign it into law, dissolve parliament, and call for an election.