Hi there, some things to think about in addition to legalities (since you mentioned about offending family) -- a deciding factor in where to get married, US vs. UK, for us was that my family is much smaller than my fiancé's.
They are also all in one local area, so it's easier to coordinate as far as flights, airport transportation, etc., whereas my fiancé's family are scattered throughout the U.K.
Also, the ability for the families to pay for the trip (flight, hotel, food, etc.) is another thing to take into account on deciding where to have the wedding.