Roaming ripoffs...
I think roaming charges should be based on the equivalent package available locally, so worst case you pay for a locally equivalent subscription for the duration of your stay or at the local prepaid rate...
As it stands, it's cheaper to simply buy a prepaid simcard and use that, but you obviously end up with a different number which can become troublesome.
You should also get a temporary local number for your stay, it seems stupid to go somewhere on business or a visit, only to have the people you're seeing forced to pay for an international call to contact you, and you then having to pay again to receive that call.
You should be able to choose the rate from the available options, just like a local can, keep your number (but pay for incoming on it) and get a local number for the duration of your stay. It could work out quite profitable for some carriers, as you'd be paying contract rates but not receiving any handset subsidy etc.
Otherwise you achieve the same effect by simply buying a local sim, tho if you don't keep going back regularly the sim expires and it can be hassle shopping around in a foreign country looking for a mobile sim.