Unfortunately, I think the answer to this question is that there is no answer to this question, each hotel is so unique and different, even within the same brand,that there is no real standard.

I think the only way to find this out is to walk through the different room catagories with the reservationist at each hotel, and ask what the differences in price will get you.

Hope this isn't off topic but I have refused upgrades because I often find that I don't always agree with the hotel as to what makes a "better" room and I really don't want a higher room in a hotel with slow elevators and no real view, or I don't want a suite at the end of those long resort corridors if I am spending most of my time in meetings in the Ballroom.

Just my 2 cents.