Gervase, if you "long to be a citizen rather than a subject", I think you have your priorities somewhat awry - would it make the slightest difference to you?My feeling is that the Royal Family, especially the current Monarch, personify and exemplify what it is to be British: just as the Americans have their flag, and swear allegiance to it, so we have the Queen. And I think we tamper with this arrangement at our peril. Look at the problems that the Labour party has with its current "reform" of the House of Lords: does anyone think that the result of their proposal will be an improvement? With constitutional change, wrecking is easy - improvement is much more difficult. I think that the R/Family ain't broke, so don't need fixing. (But then, that's what I thought about the House of Lords, too.)
I regard the effects of the R/F on tourism, etc, almost as an irrelevance: much more important things are at stake.